[llvm-branch-commits] [llvm] release/23.x: [DAGCombiner][AArch64] Fix the multiplier when folding a partial reduction of a mask (#215187) (PR #215512)

[Sander de Smalen via llvm-branch-commits]

https://github.com/sdesmalen-arm approved this pull request.

This is a bug-fix that should make it onto the release branch. It is also low risk to cherry-pick (i.e. it only affects a specific case that was broken before and is fixed by this PR)

https://github.com/llvm/llvm-project/pull/215512