Utils: Avoid RAUW on metadata in CloneFunction()

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223555 91177308-0d34-0410-b5e6-96231b3b80d8
Utils: Style cleanups, NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223556 91177308-0d34-0410-b5e6-96231b3b80d8