Fix: add the kubevirt port to the store only if it is not existed

Remove all flows before remove bridge and ports

Change-Id: I8027bc19b70dce10612f8bc32da6062937299d89
(cherry picked from commit e66ed69033b65ad8ec1c6e1405f87b9be304cfd7)
diff --git a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/KubevirtVmWatcher.java b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/KubevirtVmWatcher.java
index 43d3e64..fc3baab 100644
--- a/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/KubevirtVmWatcher.java
+++ b/apps/kubevirt-networking/app/src/main/java/org/onosproject/kubevirtnetworking/impl/KubevirtVmWatcher.java
@@ -248,7 +248,9 @@
                     port = port.updateDeviceId(deviceId);
                 }
 
-                portAdminService.createPort(port);
+                if (portAdminService.port(port.macAddress()) == null) {
+                    portAdminService.createPort(port);
+                }
             });
         }