[X86] Clear EVEX512 feature for 128-bit and 256-bit FMA intrinsics (#156472)

This matches the corresponding features defined in avx512vlintrin.h.

Author: ckoparkar

clang/lib/Headers/fmaintrin.h

@@ -15,8 +15,12 @@
 #define __FMAINTRIN_H
 
 /* Define the default attributes for the functions in this file. */
-#define __DEFAULT_FN_ATTRS128 __attribute__((__always_inline__, __nodebug__, __target__("fma"), __min_vector_width__(128)))
-#define __DEFAULT_FN_ATTRS256 __attribute__((__always_inline__, __nodebug__, __target__("fma"), __min_vector_width__(256)))
+#define __DEFAULT_FN_ATTRS128                                                  \
+  __attribute__((__always_inline__, __nodebug__, __target__("fma,no-evex512"), \
+                 __min_vector_width__(128)))
+#define __DEFAULT_FN_ATTRS256                                                  \
+  __attribute__((__always_inline__, __nodebug__, __target__("fma,no-evex512"), \
+                 __min_vector_width__(256)))
 
 #if defined(__cplusplus) && (__cplusplus >= 201103L)
 #define __DEFAULT_FN_ATTRS128_CONSTEXPR __DEFAULT_FN_ATTRS128 constexpr