[clang] [Clang] Fix 'gpuintrin.h' match when included with no arch set (PR #129927)

[Matt Arsenault via cfe-commits]

https://github.com/arsenm commented:

Should drop the nvvm reflect here. Really shouldn't have any subtarget dependent code here. Injecting implementation details into the source program is part of the fundamental issue with device lib linking 

https://github.com/llvm/llvm-project/pull/129927