Re-commit r357452: SimplifyCFG SinkCommonCodeFromPredecessors: Also sink...

Re-commit r357452: SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)

The original commit caused false positives from AddressSanitizer's
use-after-scope checks, which have now been fixed in r358478.

> The code was previously checking that candidates for sinking had exactly
> one use or were a store instruction (which can't have uses). This meant
> we could sink call instructions only if they had a use.
>
> That limitation seemed a bit arbitrary, so this patch changes it to
> "instruction has zero or one use" which seems more natural and removes
> the need to special-case stores.
>
> Differential revision: https://reviews.llvm.org/D59936

llvm-svn: 358483