[llvm] Port CodeGenPrepare to new pass manager (and BasicBlockSectionsProfil… (PR #75380)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> My apologies, I don't see the merge button. This is my first pull request on this project, where do I find the merge button?

I guess if you aren't a project member you may not see it? I still find it odd a committer still needs to hit the button after approval 

https://github.com/llvm/llvm-project/pull/75380