[llvm] [AMDGPU] Fix GCUpwardRPTracker. (PR #74328)

[Valery Pykhtin via llvm-commits]

vpykhtin wrote:

For some reason I thought it's better to fix these issues in one PR, but know I realized I can do it separately, so I'll better split this PR.

https://github.com/llvm/llvm-project/pull/74328