[llvm] AMDGPU: Add is_fpclass to isBoolSGPR (PR #141801)

[Matt Arsenault via llvm-commits]

arsenm wrote:

### Merge activity

* **May 28, 7:25 PM UTC**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/141801).


https://github.com/llvm/llvm-project/pull/141801