Revert "dwarfgen: Add support for generating the debug_str_offsets section, take 2"

This reverts commit r337933. The build error is fixed but the test now
fails on the darwin buildbots. Investigating...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@337935 91177308-0d34-0410-b5e6-96231b3b80d8
8 files changed