devstack: Update enabled services

The glance-registry service was removed some time ago.

Also, quantum was renamed to neutron and 'quantum' in enabled services
has no effect now.

Change-Id: I9f177493bb4b870c3e88741d3ffd12cd51265702

zuul.d/master_jobs.yaml

@@ -1468,7 +1468,6 @@
         mysql: true
         rabbit: true
         g-api: true
-        g-reg: true
         n-api: true
         n-cond: true
         n-cpu: true
@@ -1477,7 +1476,7 @@
         placement-api: true
         n-api-meta: true
         q-svc: true
-        quantum: true
+        neutron: true
         taas: true
         taas_openvswitch_agent: true
         tempest: true