Basic support for LISP-GPE encapsulated NSH packets

Change-Id: I97fedb0f70dd18ed9bbe985407cc5fe714e8a2e2
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vnet/gre/gre.c b/src/vnet/gre/gre.c
index 0faed13..cd43a3a 100644
--- a/src/vnet/gre/gre.c
+++ b/src/vnet/gre/gre.c
@@ -177,6 +177,9 @@
         return (GRE_PROTOCOL_teb);
     case VNET_LINK_ARP:
         return (GRE_PROTOCOL_arp);
+    case VNET_LINK_NSH:
+        ASSERT(0);
+        break;
     }
     ASSERT(0);
     return (GRE_PROTOCOL_ip4);