Always pass $NEUTRON_CONF
Always pass $NEUTRON_CONF

When running a compute node that only runs n-cpu and neutron-agent,
there are still configuration items that are needed by the agent that
reside in $NEUTRON_CONF - such as the rabbit rpc information.

Change-Id: Ib7f5dde3afb0c19dc88f351c99bc669217952a14

openstack-dev/devstack,openstack-dev/devstack,noironetworks/devstack,bigswitch/devstack,nawawi/openstack,richliu/devstack,group-policy/devstack,nawawi/openstack,noironetworks/devstack,Mahito/devstack,dtroyer/devstack,bswartz/devstack,bswartz/devstack,Mahito/devstack,group-policy/devstack,richliu/devstack,dtroyer/devstack,bigswitch/devstack