Remove cinder-volume from controller image.

The cinder-volume element will be installed as dep by either
cinder-tgt or cinder-lio. We do not want it to be deployed on the
controller nodes if one opts to use external BlockStorage nodes
and as such does not use cinder-{tgt,lio} on the controller.

Change-Id: I3d8f1af2866db5e9d061a5481eea865ba7d8b94c