Use plain intrinsic call in NEON wrappers (no :: or parens)

On MSVC ARM64, arm64_neon.h defines intrinsics as function-like macros
that expand to cast expressions starting with '('. This means:
- (OP##_u8)(a,b) → suppresses macro expansion → 'undeclared identifier'
- ::OP##_u8(a,b) → expands to ::(cast)expr → C2589 'illegal token after ::'

Since the wrapper functions now carry an x_ prefix (e.g. x_vaddq_u8),
calling the intrinsic as OP##_u8(a,b) inside the wrapper body cannot
recurse, so neither the parenthesis trick nor the :: qualifier is needed.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: AntoinePrv

include/xsimd/arch/xsimd_neon.hpp

@@ -33,15 +33,15 @@
     {                                                                                          \
         XSIMD_INLINE auto(x_##OP##_u8)(uint8x16_t a, uint8x16_t b) noexcept -> RT<uint8x16_t>  \
         {                                                                                      \
-            return ::OP##_u8(a, b);                                                            \
+            return OP##_u8(a, b);                                                            \
         }                                                                                      \
         XSIMD_INLINE auto(x_##OP##_u16)(uint16x8_t a, uint16x8_t b) noexcept -> RT<uint16x8_t> \
         {                                                                                      \
-            return ::OP##_u16(a, b);                                                           \
+            return OP##_u16(a, b);                                                           \
         }                                                                                      \
         XSIMD_INLINE auto(x_##OP##_u32)(uint32x4_t a, uint32x4_t b) noexcept -> RT<uint32x4_t> \
         {                                                                                      \
-            return ::OP##_u32(a, b);                                                           \
+            return OP##_u32(a, b);                                                           \
         }                                                                                      \
     }
 
@@ -51,15 +51,15 @@
     {                                                                                       \
         XSIMD_INLINE auto(x_##OP##_s8)(int8x16_t a, int8x16_t b) noexcept -> RT<int8x16_t>  \
         {                                                                                   \
-            return ::OP##_s8(a, b);                                                         \
+            return OP##_s8(a, b);                                                         \
         }                                                                                   \
         XSIMD_INLINE auto(x_##OP##_s16)(int16x8_t a, int16x8_t b) noexcept -> RT<int16x8_t> \
         {                                                                                   \
-            return ::OP##_s16(a, b);                                                        \
+            return OP##_s16(a, b);                                                        \
         }                                                                                   \
         XSIMD_INLINE auto(x_##OP##_s32)(int32x4_t a, int32x4_t b) noexcept -> RT<int32x4_t> \
         {                                                                                   \
-            return ::OP##_s32(a, b);                                                        \
+            return OP##_s32(a, b);                                                        \
         }                                                                                   \
     }
 
@@ -69,11 +69,11 @@
     {                                                                                          \
         XSIMD_INLINE auto(x_##OP##_u64)(uint64x2_t a, uint64x2_t b) noexcept -> RT<uint64x2_t> \
         {                                                                                      \
-            return ::OP##_u64(a, b);                                                           \
+            return OP##_u64(a, b);                                                           \
         }                                                                                      \
         XSIMD_INLINE auto(x_##OP##_s64)(int64x2_t a, int64x2_t b) noexcept -> RT<int64x2_t>    \
         {                                                                                      \
-            return ::OP##_s64(a, b);                                                           \
+            return OP##_s64(a, b);                                                           \
         }                                                                                      \
     }
 
@@ -82,7 +82,7 @@
     {                                                                                             \
         XSIMD_INLINE auto(x_##OP##_f32)(float32x4_t a, float32x4_t b) noexcept -> RT<float32x4_t> \
         {                                                                                         \
-            return ::OP##_f32(a, b);                                                              \
+            return OP##_f32(a, b);                                                              \
         }                                                                                         \
     }
 
@@ -91,27 +91,27 @@
     {                                                                        \
         XSIMD_INLINE auto(x_##OP##_u8)(uint8x16_t a) noexcept -> uint8x16_t  \
         {                                                                    \
-            return ::OP##_u8(a);                                             \
+            return OP##_u8(a);                                             \
         }                                                                    \
         XSIMD_INLINE auto(x_##OP##_s8)(int8x16_t a) noexcept -> int8x16_t    \
         {                                                                    \
-            return ::OP##_s8(a);                                             \
+            return OP##_s8(a);                                             \
         }                                                                    \
         XSIMD_INLINE auto(x_##OP##_u16)(uint16x8_t a) noexcept -> uint16x8_t \
         {                                                                    \
-            return ::OP##_u16(a);                                            \
+            return OP##_u16(a);                                            \
         }                                                                    \
         XSIMD_INLINE auto(x_##OP##_s16)(int16x8_t a) noexcept -> int16x8_t   \
         {                                                                    \
-            return ::OP##_s16(a);                                            \
+            return OP##_s16(a);                                            \
         }                                                                    \
         XSIMD_INLINE auto(x_##OP##_u32)(uint32x4_t a) noexcept -> uint32x4_t \
         {                                                                    \
-            return ::OP##_u32(a);                                            \
+            return OP##_u32(a);                                            \
         }                                                                    \
         XSIMD_INLINE auto(x_##OP##_s32)(int32x4_t a) noexcept -> int32x4_t   \
         {                                                                    \
-            return ::OP##_s32(a);                                            \
+            return OP##_s32(a);                                            \
         }                                                                    \
     }
 
@@ -121,11 +121,11 @@
     {                                                                        \
         XSIMD_INLINE auto(x_##OP##_u64)(uint64x2_t a) noexcept -> uint64x2_t \
         {                                                                    \
-            return ::OP##_u64(a);                                            \
+            return OP##_u64(a);                                            \
         }                                                                    \
         XSIMD_INLINE auto(x_##OP##_s64)(int64x2_t a) noexcept -> int64x2_t   \
         {                                                                    \
-            return ::OP##_s64(a);                                            \
+            return OP##_s64(a);                                            \
         }                                                                    \
     }
 
@@ -134,7 +134,7 @@
     {                                                                          \
         XSIMD_INLINE auto(x_##OP##_f32)(float32x4_t a) noexcept -> float32x4_t \
         {                                                                      \
-            return ::OP##_f32(a);                                              \
+            return OP##_f32(a);                                              \
         }                                                                      \
     }