[llvm] ValueTracking: Add baseline tests for minimumnum/maximumnum (PR #138736)

[Matt Arsenault via llvm-commits]

arsenm wrote:

### Merge activity

* **May 7, 1:55 AM EDT**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/138736).


https://github.com/llvm/llvm-project/pull/138736