[clang] [CMAKE][AMDGPU] fix build failure caused by PR #133619 (PR #133776)

[Slava Zakharin via cfe-commits]

vzakhari wrote:

> > @farzonl can you please revert the original commit? It seems to break just any LLVM build, so I guess the CI testing of all new PRs should be affected.
> 
> I don't see it breaking any build in LLVM, just the amd offload ones. Al the Premerge tests also passed. I suspect the `AMDGPUBot.cmake` is doing something unique. Will study it more
> 
> but the PR to revert is here #133795

Thanks! I think, it only affects the `-DBUILD_SHARED_LIBS=ON` builds, so, indeed, not all the builds :)

A couple more examples: https://lab.llvm.org/buildbot/#/builders/145/builds/6156 https://lab.llvm.org/buildbot/#/builders/89/builds/19738

https://github.com/llvm/llvm-project/pull/133776