[llvm] [OpenMP] Update atomic helpers to just use headers (PR #122185)

[Joseph Huber via llvm-commits]

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@@ -99,7 +99,7 @@ set(bc_flags -c -foffload-lto -std=c++17 -fvisibility=hidden
               ${clang_opt_flags} --offload-device-only
              -nocudalib -nogpulib -nogpuinc -nostdlibinc
              -fopenmp -fopenmp-cuda-mode
-             -Wno-unknown-cuda-version
+             -Wno-unknown-cuda-version -Wno-openmp-target
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jhuber6 wrote:

This is noise, for some reason it thinks that the `static constexpr` variables aren't on the device (they are)`. Ideally OpenMP will be removed altogether soon enough.

https://github.com/llvm/llvm-project/pull/122185