[llvm] [GISel] Enforce G_PTR_ADD RHS type matching index size for addr space (PR #84352)

[Pierre van Houtryve via llvm-commits]

https://github.com/Pierre-vh approved this pull request.

LGTM, thanks a lot for doing this, I wanted to do it but I got sidetracked and forgot about it :(

https://github.com/llvm/llvm-project/pull/84352