[llvm] [Coroutines][LazyCallGraph] resumes are not really SCC (PR #116285)

[John McCall via llvm-commits]

rjmccall wrote:

IIRC, the coro passes are trying to be cooperative by updating the call graph after splitting rather than just invalidating the analysis in its entirety. I don't think it's lowering-specific in any way. I don't have any strong opinion about how this is done, so if the code is wrong, or if it's causing more trouble than it's worth, feel free to rip it out.

https://github.com/llvm/llvm-project/pull/116285