Support -Wc++98-compat-pedantic as requested:

http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20120409/056126.html

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154655 91177308-0d34-0410-b5e6-96231b3b80d8