Set toplevel nova::dhcp_domain for all nova services

Setting nova::metadata::dhcp_domain will no longer work unless nova::metadata
is included.
Since I07caa3185427b48e6e7d60965fa3e6157457018c we no longer include
nova::metadata on computes.
So we must now set nova::dhcp_domain in nova-base instead of relying on the
deprecated nova::metadata::dhcp_domain param.

Conflicts:
  deployment/nova/nova-base-puppet.yaml

Closes-bug: #1905418
Depends-on: I98fe83e0c245388944529cd19b5e2bbed134e855
Change-Id: Iaf7823ea8d456008c1f4a3d7631657faa65eb6d3
(cherry picked from commit bf7ef6b)
(cherry picked from commit efd73e1)
(cherry picked from commit 5d62f66)

deployment/nova/nova-base-puppet.yaml

@@ -292,7 +292,7 @@ outputs:
           nova::network::neutron::neutron_project_name: 'service'
           nova::network::neutron::neutron_username: 'neutron'
           nova::network::neutron::neutron_region_name: {get_param: KeystoneRegion}
-          nova::metadata::dhcp_domain: ''
+          nova::dhcp_domain: ''
           nova::network::neutron::neutron_password: {get_param: NeutronPassword}
           nova::network::neutron::neutron_auth_url: {get_param: [EndpointMap, KeystoneV3Internal, uri]}
           nova::rabbit_heartbeat_timeout_threshold: 60