[llvm] [SelectionDAG] Scalarize binary ops of splats before legal types (PR #100749)

[via llvm-commits]

Fros1er wrote:

> Also I hope you don't mind but I updated the PR title to add a tag, https://llvm.org/docs/DeveloperPolicy.html#id18

Sorry, I forgot to add the tag when I submitted...

> Do you need someone to land this for you?

Yes, as I don't have write access. Thanks!

https://github.com/llvm/llvm-project/pull/100749