[clang] [CUDA][NFC] CudaArch to GpuArch rename (PR #97028)

[Matt Arsenault via cfe-commits]

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@@ -52,7 +52,7 @@ const char *CudaVersionToString(CudaVersion V);
 // Input is "Major.Minor"
 CudaVersion CudaStringToVersion(const llvm::Twine &S);
 
-enum class CudaArch {
+enum class GpuArch {
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arsenm wrote:

Probably should call this OffloadArch to match --offload-arch 

https://github.com/llvm/llvm-project/pull/97028