[llvm] [MachinePipeliner] Fix store-store dependences (#72508) (PR #72575)

[via llvm-commits]

bcahoon wrote:

Hi @ytmukai, are you ok with merging this. Your previous comment raises a concern about getIncrementValue(). I think the two changes are independent - this change is for a correctness issue and the implementation of getIncrementValue is to improve performance. Thoughts?

https://github.com/llvm/llvm-project/pull/72575