[clang] [HIP][Test] Fix hip-include-path.hip fail when AMDGPU isn't in LLVM_TARGETS_TO_BUILD (PR #214656)

[Yaxun Liu via cfe-commits]

yxsamliu wrote:

Thanks for the fix. I think this is no longer needed after #214612 removed the device compilation that caused the failure. The remaining `-###` tests should still work without the AMDGPU backend.

https://github.com/llvm/llvm-project/pull/214656