[llvm] [DebugInfo][LoopLoadElim] Fix missing debug location updates (PR #91839)

[Orlando Cazalet-Hyams via llvm-commits]

https://github.com/OCHyams commented:

Thanks for the patch!

Test LGTM. There are just a couple of minor nits and a question about whether the phi location to address.

https://github.com/llvm/llvm-project/pull/91839