Avoid invalid compiler options for MSVC

Fixes open-quantum-safe#2238

Author: matlimatli

src/common/CMakeLists.txt

@@ -26,8 +26,13 @@ else()
    if (OQS_DIST_X86_64_BUILD OR OQS_USE_AES_INSTRUCTIONS)
       set(AES_IMPL ${AES_IMPL} aes/aes128_ni.c)
       set(AES_IMPL ${AES_IMPL} aes/aes256_ni.c)
-      set_source_files_properties(aes/aes128_ni.c PROPERTIES COMPILE_FLAGS "-maes -mssse3")
-      set_source_files_properties(aes/aes256_ni.c PROPERTIES COMPILE_FLAGS "-maes -mssse3")
+      if(CMAKE_C_COMPILER_ID STREQUAL "MSVC")
+        set_source_files_properties(aes/aes128_ni.c PROPERTIES COMPILE_FLAGS "")
+        set_source_files_properties(aes/aes256_ni.c PROPERTIES COMPILE_FLAGS "")
+      else()
+        set_source_files_properties(aes/aes128_ni.c PROPERTIES COMPILE_FLAGS "-maes -mssse3")
+        set_source_files_properties(aes/aes256_ni.c PROPERTIES COMPILE_FLAGS "-maes -mssse3")
+      endif()
    elseif (OQS_DIST_ARM64_V8_BUILD)
       set(AES_IMPL ${AES_IMPL} aes/aes128_armv8.c)
       set(AES_IMPL ${AES_IMPL} aes/aes256_armv8.c)