[llvm] [coro][pgo] Don't promote pgo counters in the suspend basic block (PR #71263)

[Mircea Trofin via llvm-commits]

mtrofin wrote:

> In fact, there are other passes failed to handle the suspend intrinsic. Originally we were wondering if we can fix the issues by providing a new analysis pass (e.g., CoroInfoPass). But we failed to go on (due to limited development resources). So it sounds a good idea to extract the common patterns to common utilities. Although I don't think this should be a requirement for this specific PR.  

Ack. Is there a Discourse topic on this, otherwise I can start one. We could, for example, add a IR validation clause, too.

https://github.com/llvm/llvm-project/pull/71263