[clang] [HLSL][clang] Add elementwise builtin for atan2 (p3) (PR #110187)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only -disable-llvm-passes -verify -DTEST_FUNC=__builtin_elementwise_atan2
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only -disable-llvm-passes -verify -DTEST_FUNC=__builtin_elementwise_pow
+
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farzonl wrote:

add 
```suggestion
// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only -disable-llvm-passes -verify -DTEST_FUNC=__builtin_elementwise_fmod
```
delete the  https://github.com/llvm/llvm-project/blob/main/clang/test/SemaHLSL/BuiltIns/fmod-errors.hlsl file

https://github.com/llvm/llvm-project/pull/110187