[llvm] Clean up strange uses of getAnalysisIfAvailable (PR #65729)

[Björn Pettersson via llvm-commits]

bjope wrote:

> > I guess I don't know how pull requests and reviewing works in github. I actually added 3 comments on this patch a several days (or weeks) ago. But turns out that they were "pending" because I had only "started review" and not found the place to "submit review".
> 
> For that reason I usually click "add single comment" instead of "start a review".

Thanks. I'll try to remember that.

If they for example had named the buttons "Post comment directly" and "Save as draft", then it has been more obvious.
I also do not know how to find all my pending "draft reviews" (unless I'm already "assigned" or "requested as reviewer") as the https://github.com/pulls is just crap compared to my old dashboard in phabricator.

https://github.com/llvm/llvm-project/pull/65729