[clang] Add _MM_FROUND_TIES_TO_EVEN to avx512fintrin.h (PR #99691)

[Simon Pilgrim via cfe-commits]

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@@ -43,6 +43,7 @@ typedef unsigned short __mmask16;
 
 /* Rounding mode macros.  */
 #define _MM_FROUND_TO_NEAREST_INT   0x00
+#define _MM_FROUND_TIES_TO_EVEN     0x00
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RKSimon wrote:

(very pedantic) but _MM_FROUND_TO_NEAREST_TIES_EVEN would more closely keep to the existing `_MM_FROUND_TO_*` naming scheme

https://github.com/llvm/llvm-project/pull/99691