Fixed to trigger correct event when a gateway removed

Change-Id: Icae28da520dbe6b4e2fd5be998aa2f85c8abdd15
diff --git a/apps/openstacknetworking/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java b/apps/openstacknetworking/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java
index 6b10512..3262969 100644
--- a/apps/openstacknetworking/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java
+++ b/apps/openstacknetworking/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java
@@ -305,7 +305,7 @@
             }
             if (oldGateway != null && newGateway == null) {
                 notifyDelegate(new OpenstackRouterEvent(
-                        OPENSTACK_ROUTER_GATEWAY_ADDED,
+                        OPENSTACK_ROUTER_GATEWAY_REMOVED,
                         event.newValue().value(), oldGateway));
             }
         }