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_entry_src_interface.c b/src/vnet/fib/fib_entry_src_interface.c
index bb87818..6c087f3 100644
--- a/src/vnet/fib/fib_entry_src_interface.c
+++ b/src/vnet/fib/fib_entry_src_interface.c
@@ -35,7 +35,7 @@
 fib_entry_src_interface_add (fib_entry_src_t *src,
                              const fib_entry_t *entry,
                              fib_entry_flag_t flags,
-                             fib_protocol_t proto,
+                             dpo_proto_t proto,
                              const dpo_id_t *dpo)
 {
     src->fes_pl = fib_path_list_create_special(