[llvm] [VPlan] Hook IR blocks into VPlan during skeleton creation (NFC) (PR #114292)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

The latest version now also updated the VPlan printing tests and moved final printing to VPlan::execute to also capture the updated skeleton

https://github.com/llvm/llvm-project/pull/114292