[llvm] [VPlan] Introduce scalar loop header in plan, remove VPLiveOut. (PR #109975)

[Kirill Stoimenov via llvm-commits]

kstoimenov wrote:

Looks like there is still one more leak left after your fix: https://lab.llvm.org/buildbot/#/builders/169/builds/4871/steps/10/logs/stdio

https://github.com/llvm/llvm-project/pull/109975