Handled exception case of OpenStack network type

Ignore the network with unsupported network type to make sure no flow rules
populated for the network by any chance.

Change-Id: I3fe01900e5239af1ea28f4c6cb95869ff47964a9
diff --git a/apps/openstackswitching/api/src/main/java/org/onosproject/openstackswitching/OpenstackNetwork.java b/apps/openstackswitching/api/src/main/java/org/onosproject/openstackswitching/OpenstackNetwork.java
index 181caf8..c760146 100644
--- a/apps/openstackswitching/api/src/main/java/org/onosproject/openstackswitching/OpenstackNetwork.java
+++ b/apps/openstackswitching/api/src/main/java/org/onosproject/openstackswitching/OpenstackNetwork.java
@@ -36,10 +36,7 @@
         /**
          * Currently only VXLAN moded is supported.
          */
-        VXLAN,
-        VLAN,
-        STT,
-        LOCAL
+        VXLAN
     }
 
     /**