specify dwarf version for Solaris

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219901 91177308-0d34-0410-b5e6-96231b3b80d8
Frontend: Fix some underscore-then-capital UB

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219903 91177308-0d34-0410-b5e6-96231b3b80d8