[llvm] [DAG] Matched FixedWidth pattern for ISD::AVGFLOORU (PR #84903)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

Thanks, this LGTM now if others agree.

LLVM tends to prefer early exits to nested if's, but in this case if you are adding AVGCEIL in another patch then it could be handled in this same function, where the if's make sense.

https://github.com/llvm/llvm-project/pull/84903