[llvm] [LegalizeTypes] Create an ISD::ADD instead of an ISD::UADDO with unused overflow result. (PR #100647)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon approved this pull request.

LGTM - I can't find anything that uses ExpandIntRes_ADDSUB that assumes there's a overflow value(1).

https://github.com/llvm/llvm-project/pull/100647