[clang] [clang-tools-extra] [Clang] Use TargetInfo when deciding if an address space is compatible (PR #115777)

[John McCall via cfe-commits]

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

Code LGTM. I would still prefer this PR to just contain the NFC refactor, with a follow up that adds the semantic changes to the AMDGPU and NVPTX targets.

https://github.com/llvm/llvm-project/pull/115777