[clang] [Headers][X86] Allow SSE2/AVX2/AVX512F/AVX512BW/AVX512DQ integer arithmetic intrinsics to be used in constexpr (PR #157582)

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donneypr wrote:

@RKSimon from what I can see in clang/lib/Headers/mmintrin.h, it looks like all the intrinsics you mentioned are already being used in CONSTEXPR, shall I make test cases for it?

Thanks for providing the test cases for the others, I will get them in the right builtins file and get back to you

https://github.com/llvm/llvm-project/pull/157582