Update TargetTriple format info.
Phabricator revision: http://reviews.llvm.org/D6543

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223473 91177308-0d34-0410-b5e6-96231b3b80d8
Small cleanup on how we clear constant variables. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223474 91177308-0d34-0410-b5e6-96231b3b80d8