Extend noinline to gcc >= 12 to fix -Werror=maybe-uninitialized false positives in gcc 15 (#311)

A build failure can be reproduced with colcon's `--mixin coverage-gcc`
(or `-DCMAKE_C_FLAGS='--coverage' -DCMAKE_CXX_FLAGS='--coverage'`) on
Ubuntu 26.04, which has gcc 15.2.0 by default.

Signed-off-by: Christophe Bedard <bedard.christophe@gmail.com>

Author: christophebedard

include/fastcdr/xcdr/optional.hpp

@@ -92,10 +92,10 @@ class optional
 
     //! Destructor
     ~optional()
-#if defined(__GNUC__) && __GNUC__ == 12
+#if defined(__GNUC__) && __GNUC__ >= 12
     __attribute__(
         (noinline))
-#endif // if defined(__GNUC__) && __GNUC__ == 12
+#endif // if defined(__GNUC__) && __GNUC__ >= 12
     = default;
 
     /*!
@@ -212,10 +212,10 @@ class optional
     //! Assigns content from an optional.
     optional& operator =(
             const optional& opt)
-#if defined(__GNUC__) && __GNUC__ == 12
+#if defined(__GNUC__) && __GNUC__ >= 12
     __attribute__(
             (noinline))
-#endif // if defined(__GNUC__) && __GNUC__ == 12
+#endif // if defined(__GNUC__) && __GNUC__ >= 12
     {
         reset();
         storage_.engaged_ = opt.storage_.engaged_;
@@ -229,10 +229,10 @@ class optional
     //! Assigns content from an optional.
     optional& operator =(
             optional&& opt)
-#if defined(__GNUC__) && __GNUC__ == 12
+#if defined(__GNUC__) && __GNUC__ >= 12
     __attribute__(
             (noinline))
-#endif // if defined(__GNUC__) && __GNUC__ == 12
+#endif // if defined(__GNUC__) && __GNUC__ >= 12
     {
         reset();
         storage_.engaged_ = opt.storage_.engaged_;