sr: srv6 path tracing api

Implements the API for SRv6 Path Tracing

Type: feature

Signed-off-by: Julian Klaiber <julian@klaiber.me>
Change-Id: Iefa7e512c8e1894595a9e3f5d42eab4160db1f28
diff --git a/src/vnet/srv6/sr_pt.h b/src/vnet/srv6/sr_pt.h
index cd70cd0..53001e1 100644
--- a/src/vnet/srv6/sr_pt.h
+++ b/src/vnet/srv6/sr_pt.h
@@ -75,6 +75,8 @@
   /* Hash table for sr_pt_iface parameters */
   mhash_t sr_pt_iface_index_hash;
 
+  /* convenience */
+  u16 msg_id_base;
 } sr_pt_main_t;
 
 extern sr_pt_main_t sr_pt_main;