Fix: resolve a set of NPEs and WARNs caused by null instance port

Change-Id: I62b1c21cb9fac7d38924e85838a435737664f6c0
diff --git a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java
index bea2a00..d16647c 100644
--- a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java
+++ b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/DistributedOpenstackRouterStore.java
@@ -321,7 +321,8 @@
         }
     }
 
-    private class OpenstackRouterInterfaceMapListener implements MapEventListener<String, RouterInterface> {
+    private class OpenstackRouterInterfaceMapListener
+                        implements MapEventListener<String, RouterInterface> {
 
         @Override
         public void event(MapEvent<String, RouterInterface> event) {
@@ -360,7 +361,8 @@
         }
     }
 
-    private class OpenstackFloatingIpMapListener implements MapEventListener<String, NetFloatingIP> {
+    private class OpenstackFloatingIpMapListener
+                            implements MapEventListener<String, NetFloatingIP> {
 
         @Override
         public void event(MapEvent<String, NetFloatingIP> event) {