[clang] [Clang][ARM] Only try to redefine builtins for non-CUDA (PR #128222)

[Joseph Huber via cfe-commits]

https://github.com/jhuber6 approved this pull request.

Maybe a comment for why we need to check for the CUDA arch, but I'll defer to @Artem-B for the final +1.

https://github.com/llvm/llvm-project/pull/128222