Revert "[InstCombine] reduce even more unsigned saturated add with 'not' op"

This reverts commit 079b610c29b4a428b3ae7b64dbac0378facf6632.
Bots are failing after this change on a stage 2 compile of clang.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354277 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed