[llvm] [SCEV] Apply loop guards to End in computeMaxBECountForLT (PR #116187)

[Luke Lau via llvm-commits]

lukel97 wrote:

The pre-merge CI has picked up a lot more tests that have changed that I completely forgot to run locally, my bad. I'll check the diffs on my end and then update this PR soon

https://github.com/llvm/llvm-project/pull/116187