On a HA setup, if only contrail HA is enabled, openstackrc's auth ip is not set correctly

[Vedamurthy Joshi]

In the below setup, the openstack node is not one of the 3 Contrail HA nodes.
In such a setup, openstackrc's OS_AUTH_URL is not set correctly
It uses the internal vip (192.251 IP below) instead of the openstack node which has keystone.

https://github.com/Juniper/contrail-provisioning/blob/master/contrail_provisioning/config/scripts/quantum-server-setup.sh#L62

env.roledefs = {
    'all': [host1, host2, host3, host4, host5, host6, host7],
    'cfgm': [host1, host2, host3],
    'openstack': [host7],
    'webui': [host2],
    'control': [host1, host2, host3],
    'compute': [host4, host5, host6],
    'collector': [host1, host2, host3],
    'database': [host1, host2, host3],
    'build': [host_build],
    'toragent': [host5, host6],
    'tsn': [host5, host6],
}

env.hostnames = {
    'all': ['testbed-1-vm1', 'testbed-1-vm2', 'testbed-1-vm3', 'nodei1', 'nodei2', 'nodei3', 'nodeg36']
}
env.ha = {
    'contrail_internal_vip' : '192.168.192.251',
}