[llvm] [Hexagon] Fix hwloop trip count for post-increment load induction (PR #225411)

[Brian Cain via llvm-commits]

https://github.com/androm3da approved this pull request.

LGTM

Can you remind me where we encountered this?  Was it a regression?  Should  we cherry-pick to 23.x?

https://github.com/llvm/llvm-project/pull/225411