[util] update on DirName() on BSD-derived system

This is a follow-up to e201c15715834f925624463a7ccac8d59c3464eb.

Change-Id: Ic70ea96640d281bda372bd54c7d67bb1a59e0a8b
Reviewed-on: http://gerrit.cloudera.org:8080/16467
Tested-by: Kudu Jenkins
Reviewed-by: Grant Henke <granthenke@apache.org>
1 file changed