[llvm] [DAG] Refactor X86 combineVSelectWithAllOnesOrZeros fold into a generic DAG Combine (PR #145298)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

>     2. for andnot, just keep in x86 backend.

why can't we wrap this in a TLI.hasAndNot check and create `DAG.getNode(ISD::AND, dl, VL, DAG.getNOT(X), Y)` ?

https://github.com/llvm/llvm-project/pull/145298