Currently the qemu-img package is not installed by default for a cinder-volume node. This causes cinder to fail when trying to create images using the qemu-img command. This patch will change the 'cinder_volume_packages' attribute to also install the qemu-img package for cinder-volume nodes. Change-Id: Idb923f3edfa39720178e498433d94e4e37a76f7d Closes-bug: #1413088