[llvm-branch-commits] [NFC][msan] Extract `handleSelectLikeInst` (PR #94881)

[Vitaly Buka via llvm-branch-commits]

https://github.com/vitalybuka created https://github.com/llvm/llvm-project/pull/94881

`blendv` instructions are very similar to `select`.
We will add support for them in followup patches.