[llvm] AMDGPU: Refine gfx950 xdl-write-vgpr hazard cases (PR #117285)

[Matt Arsenault via llvm-commits]

arsenm wrote:

### Merge activity

* **Nov 25, 12:19 PM EST**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/117285).


https://github.com/llvm/llvm-project/pull/117285