The .dwo section shouldn't contain the unrelocated values (and
therefore not at all) of the pc or statement list. We also don't
need to emit the compilation dir so save so space and time
and don't bother.

Fix up the testcase accordingly and verify that we don't emit
the attributes or the items that they use.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179114 91177308-0d34-0410-b5e6-96231b3b80d8