Reland "[InstCombine] Recognize `((x * y) s/ x) !=/== y` as an signed...

Reland "[InstCombine] Recognize `((x * y) s/ x) !=/== y` as an signed multiplication overflow check (PR48769)"

This reverts commit 91f7a4ff,
relanding commit 13ec913b.

The original commit was reverted because of (essentially)
https://bugs.llvm.org/show_bug.cgi?id=35922
which has now been addressed by d0eeb64b.