libvirt: test to make sure volume_use_multipath is properly used
libvirt: test to make sure volume_use_multipath is properly used

There was no direct test for the libvirt.volume_use_multipath
config option being used with the libvirt driver to get volume
host connector properties from os-brick.

This adds a unit test which sets the config option both ways before
getting the connector properties and asserts the resulting value
is the same as the config option value.

Change-Id: If2b4cc477b4e7926bb2749db1eb4de2c6f694735
Related-Bug: #1723928

phenoxim/nova,mikalstill/nova,gooddata/openstack-nova,openstack/nova,gooddata/openstack-nova,mahak/nova,openstack/nova,mahak/nova,openstack/nova,mikalstill/nova,klmitch/nova,mikalstill/nova,mahak/nova,rahulunair/nova,phenoxim/nova,klmitch/nova,klmitch/nova,rahulunair/nova,gooddata/openstack-nova,klmitch/nova,rahulunair/nova,gooddata/openstack-nova