[llvm] [VectorCombine] foldPermuteOfBinops - fold "shuffle (binop (shuffle, other)), undef" --> "binop (shuffle), (shuffle)". (PR #122118)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

> It appears that the bot stayed red after this patch landed.

cheers - fix incoming

https://github.com/llvm/llvm-project/pull/122118