Enable plugin for fwaas multinode tests
Enable plugin for fwaas multinode tests

The multinode test definiton for neutron-fwaas omitted proper loading of
the neutron-fwaas plugin.

Change-Id: Ic898203c58ea390f11b53b91e29d18fc4585ab9e

openstack-infra/project-config,Tesora/tesora-project-config,Tesora/tesora-project-config,openstack-infra/project-config