[llvm] [VPlan] Version VPValue names in VPSlotTracker. (PR #81411)

[via llvm-commits]

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

LGTM, thanks for accommodating!
Spotted a few minor typos.

Would be good to follow-up by introducing another VPSlotTracker constructor to simplify getOrCreateName() into getName(), and by removing the useless Name of VPInstruction.

https://github.com/llvm/llvm-project/pull/81411