Revert "[ObjectYAML] Support for DWARF line tables"

This reverts commit r291541.

Still failing on a bot:

http://bb.pgr.jp/builders/cmake-llvm-x86_64-linux/builds/47224/steps/test_llvm/logs/stdio

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291542 91177308-0d34-0410-b5e6-96231b3b80d8