MPLS tunnel dump: use sw_if_index not tunnel_index

Change-Id: I6c0d5aec6ee96a0d40358f0e09a0901b22265063
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
diff --git a/src/vnet/mpls/mpls_tunnel.h b/src/vnet/mpls/mpls_tunnel.h
index 285817c..5685a0d 100644
--- a/src/vnet/mpls/mpls_tunnel.h
+++ b/src/vnet/mpls/mpls_tunnel.h
@@ -117,6 +117,11 @@
                                          fib_route_path_t *rpath);
 
 /**
+ * @vrief return the tunnel index from the sw_if_index
+ */
+extern int vnet_mpls_tunnel_get_index (u32 sw_if_index);
+
+/**
  * @brief Delete an MPLS tunnel
  */
 extern void vnet_mpls_tunnel_del (u32 sw_if_index);