Improve test coverage of nova.privsep.utils.
Improve test coverage of nova.privsep.utils.

Trivial, but makes testing coverage for this file complete.

Change-Id: Ie3a7ac393a558e450fba5f51b05ffae7f73a32a4

mahak/nova,rahulunair/nova,openstack/nova,openstack/nova,klmitch/nova,mahak/nova,rahulunair/nova,rahulunair/nova,klmitch/nova,openstack/nova,mahak/nova,klmitch/nova,klmitch/nova