Drop redundant rpms from nova-base package list
Drop redundant rpms from nova-base package list

- openstack-base explictly pulls in python[3]-keystoneclient
- openstack-base pulls in python[3]-openstackclient which
  pulls in python[3]-cinderclient

This simplifies the python2/3 cases, and reduces how many
times these 2 packages are installed

Change-Id: If8eb4dc1c5d5de88a8d9b59920b01d09cb585ebb

openstack/kolla,stackforge/kolla,rahulunair/kolla,openstack/kolla,stackforge/kolla,rahulunair/kolla,stackforge/kolla