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/ah_decrypt.c b/src/vnet/ipsec/ah_decrypt.c
index cf95588..e68accd 100644
--- a/src/vnet/ipsec/ah_decrypt.c
+++ b/src/vnet/ipsec/ah_decrypt.c
@@ -259,12 +259,9 @@
 	    }
 
 	  /* for IPSec-GRE tunnel next node is ipsec-gre-input */
-	  if (PREDICT_FALSE
-	      ((vnet_buffer (i_b0)->ipsec.flags) &
-	       IPSEC_FLAG_IPSEC_GRE_TUNNEL))
+	  if (PREDICT_FALSE (ipsec_sa_is_set_IS_GRE (sa0)))
 	    next0 = AH_DECRYPT_NEXT_IPSEC_GRE_INPUT;
 
-
 	  vnet_buffer (i_b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 	trace:
 	  if (PREDICT_FALSE (i_b0->flags & VLIB_BUFFER_IS_TRACED))