With option OptForSize enabled, the Loop Vectorizer is not supposed to
create tail loop. The condition checking that was invalid and was not
matching to the comment above.
Patch by Marianne Mailhot-Sarrasin.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240556 91177308-0d34-0410-b5e6-96231b3b80d8
