[llvm] [LV] Skip low-trip count logic there is no scalar tail (PR #225633)

[Sander de Smalen via llvm-commits]

https://github.com/sdesmalen-arm approved this pull request.

LGTM with the other condition (tripcount divides with remainder of 0) handled as part of #226318.

https://github.com/llvm/llvm-project/pull/225633