[llvm] [ctx_prof] Factor the callsite instrumentation exclusion criteria (PR #108471)

[Teresa Johnson via llvm-commits]

teresajohnson wrote:

> Reusing this in the logic fetching the instrumentation in `CtxProfAnalysis`

Do you mean it will be reused in a future patch? Because I only see the one use here.

https://github.com/llvm/llvm-project/pull/108471