Fix incorrect usage of assertEqual() method in RBD unit tests
Fix incorrect usage of assertEqual() method in RBD unit tests

This patch is to fix some incorrect usage of assertEqual() method in RBD
unit tests, and the right way is to use with assertEqual(expected, actual).

Change-Id: Ib38890e5cffbbd5dd2c31fad35bfba442519df26

j-griffith/cinder,j-griffith/cinder,openstack/cinder,phenoxim/cinder,phenoxim/cinder,mahak/cinder,openstack/cinder,mahak/cinder