[llvm] [PGO] Drive profile validator from opt (PR #147418)

[Mircea Trofin via llvm-commits]

mtrofin wrote:

### Merge activity

* **Jul 26, 2:12 PM UTC**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/147418).


https://github.com/llvm/llvm-project/pull/147418