Updated openstack/openstack
Project: openstack/cinder  7975b465d05dba38e8c4f9753f15cea6ed057a86

Switch to use oslo.db

oslo.db first stable release has been cut and we can start using it
instead of openstack/common/db/* code which is now marked obsolete.

Change-Id: Ib350e8d1dcec3be707e3b1679c70202619256269