[Neutron] neutron-rpc-server is not a configurable service

The "neutron-rpc-server" is not a configurable service that can be
enabled or disabled. This service is a dependant process of the
"neutron-api-server" service that is spawned when the Neutron API
uses the WSGI module. The execution of this child service will depend
on:
* The Neutron API service when running with the WSGI module. If
  the Neutron API uses the eventlet module, this service won't run
  (the RPC workers will be spawned by the eventlet server).
* The "rpc_workers" configuration variable. If this variable is
  explicitly set to "0", the server must not run.

Closes-Bug: #2073844
Related-Bug: #2073572
Change-Id: Ic019423ca033ded8609d82bb11841b975862ac14

Author: ralonsoh

lib/neutron

@@ -471,7 +471,7 @@ function configure_neutron {
     # (NEUTRON_DEPLOY_MOD_WSGI=True) for the Neutron server.
     local rpc_workers
     rpc_workers=$(iniget_multiline /etc/neutron/neutron.conf DEFAULT rpc_workers)
-    if ! is_service_enabled neutron-rpc-server || [ "$rpc_workers" -eq "0" ]; then
+    if [ "$rpc_workers" == "0" ]; then
         _Q_RUN_RPC_SERVER=False
     fi