[llvm] [llvm][offload] Move AMDGPU offload utilities to LLVM (PR #102487)

[Joseph Huber via llvm-commits]

https://github.com/jhuber6 commented:

We already have `Utils` somewhere else in this directory right? If we're namespacing it with `amdgpu` we could probably just put it there.

https://github.com/llvm/llvm-project/pull/102487