[llvm] [LV] Update incoming blocks in VPWidenPHIRecipe in reassociateBlocks (PR #125481)

[Luke Lau via llvm-commits]

lukel97 wrote:

I thought I had responded to the comments + pushed my changes earlier, but turns out GitHub was stuck "processing updates" so it didn't show up in the PR, sorry about that. I had to push an empty commit to get things to refresh

https://github.com/llvm/llvm-project/pull/125481