Revert 217719, that wasn't the right fix, that should complete user names, and
anyway /Vol doesn't complete correctly either.  Somehow we're chopping the names
up incorrectly before passing them into the completer.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@217720 91177308-0d34-0410-b5e6-96231b3b80d8