[llvm] LVer: improve a test, regen with UTC (PR #122876)

[David Sherwood via llvm-commits]

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

LGTM, although perhaps you should amend the title to avoid abbreviations so it's easier to search for, i.e. "LoopVersioning: ". Also, can you mention somewhere in the commit message or title that you're not just regenerating the test but also changing undef -> poison. It's not mentioned anywhere, thanks!

https://github.com/llvm/llvm-project/pull/122876