Fix nova fake driver support

Recent code updates[1][2] broke the support for nova fake drivers.
in [1], nova_services dict is introduce but the change is not refected
in nova.conf.j2[3] when dealing with its elements.
in [2], two typos make neutron handlers to fail.

[1]: https://review.openstack.org/#/c/407416/
[2]: https://review.openstack.org/#/c/424504/
[3]:
https://github.com/openstack/kolla-ansible/blob/master/ansible/roles/nova/templates/nova.conf.j2#L35

Change-Id: Ie32c76c4c902f1d95a1b4c97f8cbdb7ab101e48b
Closes-bug: #1695218