ipsec: VPP-1308 fix sorting of SPD entries

Change-Id: I761aced55b7cef51a9b47048283b2cb9430bcde2
Signed-off-by: Klement Sekera <ksekera@cisco.com>
diff --git a/src/vnet/ipsec/ipsec.h b/src/vnet/ipsec/ipsec.h
index 5b54832..404756a 100644
--- a/src/vnet/ipsec/ipsec.h
+++ b/src/vnet/ipsec/ipsec.h
@@ -299,6 +299,9 @@
 
   /* callbacks */
   ipsec_main_callbacks_t cb;
+
+  /* helper for sort function */
+  ipsec_spd_t *spd_to_sort;
 } ipsec_main_t;
 
 extern ipsec_main_t ipsec_main;