[llvm] [ctx_prof] Insert the ctx prof flattener after the module inliner (PR #107499)

[Mircea Trofin via llvm-commits]

mtrofin wrote:

> what is problem with ICP?

There's no problem, but I need to add a criteria for when to ICP, and that would increase the size of this patch. That's why it's punted.

https://github.com/llvm/llvm-project/pull/107499