[llvm] [ctx_prof] Automatically convert available external linkage to local for modules with contextual roots (PR #109203)

[Mircea Trofin via llvm-commits]

mtrofin wrote:

### Merge activity

* **Sep 24, 4:17 PM EDT**: @mtrofin started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/109203).


https://github.com/llvm/llvm-project/pull/109203