[clang] [llvm] [HLSL] Add InterlockedAdd HLSL functions (PR #195742)

[Deric C. via cfe-commits]

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Icohedron wrote:

I only see tests for groupshared memory. There should be a test for device memory too. 
This applies to both the SPIRV and DirectX tests.

https://github.com/llvm/llvm-project/pull/195742