Minor tweaks in public headers and a few .cpp files so that LLVM can build
successfully with -pedantic and projects using LLVM with -pedantic don't
get warnings from LLVM. There's still more -pedantic warnings to fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28453 91177308-0d34-0410-b5e6-96231b3b80d8