[llvm] [ctx_prof] API to get the instrumentation of a BB (PR #105468)

[Mircea Trofin via llvm-commits]

mtrofin wrote:

### Merge activity

* **Aug 21, 8:16 PM EDT**: @mtrofin started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/105468).


https://github.com/llvm/llvm-project/pull/105468