L2 over MPLS

[support for VPWS/VPLS]
- switch to using dpo_proto_t rather than fib_protocol_t in fib_paths so that we can describe L2 paths
- VLIB nodes to handle pop/push of MPLS labels to L2

Change-Id: Id050d06a11fd2c9c1c81ce5a0654e6c5ae6afa6e
Signed-off-by: Neale Ranns <nranns@cisco.com>
diff --git a/src/vnet/fib/fib_path_ext.c b/src/vnet/fib/fib_path_ext.c
index 26f2b9b..4438671 100644
--- a/src/vnet/fib/fib_path_ext.c
+++ b/src/vnet/fib/fib_path_ext.c
@@ -191,6 +191,9 @@
     case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
         parent_fct = child_fct;
 	break;
+    case FIB_FORW_CHAIN_TYPE_ETHERNET:
+        parent_fct = FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS;
+	break;
     default:
         return (nhs);
 	break;