Fix the LibcxxAndAbiBuilder's passing of LIT arguments

This removes a set of quotes that was causing lit.py to barf.

http://reviews.llvm.org/D5371


git-svn-id: https://llvm.org/svn/llvm-project/zorg/trunk@217896 91177308-0d34-0410-b5e6-96231b3b80d8