Currently neutron-server-ovn container does not run db setup for networking-ovn
subproject when bootstrapping - since it uses extend_start from
neutron-server (where networking-ovn is not installed).
Since OVN is being added as in-tree driver to Neutron and there is no
rationale behind supporting separate container images for neutron-server-ovn
and neutron-metadata-agent-ovn, hile networking-ovn driver uses around 1-2MB
of space - this change adds networking-ovn installation to neutron-base image
and deprecates neutron-server-ovn and neutron-metadata-agent-ovn images.
Change-Id: Ib2dbdd7e7d34f56985b7a5b2494c3b89034688cb
17982e5817