move group twiddling options into Diagnostic.cpp instead of
Warnings.cpp.  Warnings.cpp now doesn't need to #include
tblgen produced output directly.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@69559 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed