[llvm] [BranchFolding] Remove getBranchDebugLoc() (PR #114613)

[Jeremy Morse via llvm-commits]

https://github.com/jmorse commented:

This makes sense to me; @SLTozer has been thinking about branch-source-loc merging recently, there aren't any concerns with more parts of LLVM merging branch-source-locs together are there?

This may seem nitpicky, but I'd much prefer using explicit `DebugLoc` rather than `auto` for this code: I don't believe there's any ergonomic benefit from using `auto` here aside from fewer characters on some already small lines, and it un-necessarily obscures what's going on. Specifically, those who aren't familiar with the LLVM code base will find this harder to deal with, in exchange for very little benefit overall. (IMHO, YMMV)

https://github.com/llvm/llvm-project/pull/114613