IPSEC-GRE: fixes and API update to common types.

Change-Id: Icdcbac7453baa837a9c0c4a2401dff4a6aa6cba0
Signed-off-by: Neale Ranns <nranns@cisco.com>
diff --git a/src/vnet/ipsec-gre/ipsec_gre.c b/src/vnet/ipsec-gre/ipsec_gre.c
index e4f5e80..cdb23dd 100644
--- a/src/vnet/ipsec-gre/ipsec_gre.c
+++ b/src/vnet/ipsec-gre/ipsec_gre.c
@@ -106,8 +106,7 @@
   vnet_interface_output_runtime_t *rd = (void *) node->runtime_data;
   ipsec_gre_tunnel_t *t = pool_elt_at_index (igm->tunnels, rd->dev_instance);
 
-  /* use an ethertype of 0x01 for l2-gre */
-  u16 l2_gre_protocol_ethertype = clib_net_to_host_u16 (0x01);
+  u16 l2_gre_protocol_ethertype = clib_net_to_host_u16 (GRE_PROTOCOL_teb);
 
   /* Vector of buffer / pkt indices we're supposed to process */
   from = vlib_frame_vector_args (frame);