Remove unused arguments.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179217 91177308-0d34-0410-b5e6-96231b3b80d8
For split dwarf we should also run the objcopy action if we're
just assembling a file and have passed the option.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179218 91177308-0d34-0410-b5e6-96231b3b80d8