Remove unused argument to vlib_feature_next

Change-Id: Ieb8b53977fc8484c19780941e232ee072b667de3
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vnet/ip/ip6_reassembly.c b/src/vnet/ip/ip6_reassembly.c
index e84daf6..72df29c 100644
--- a/src/vnet/ip/ip6_reassembly.c
+++ b/src/vnet/ip/ip6_reassembly.c
@@ -990,8 +990,7 @@
 	      n_left_to_next -= 1;
 	      if (is_feature && IP6_ERROR_NONE == error0)
 		{
-		  vnet_feature_next (vnet_buffer (b0)->sw_if_index[VLIB_RX],
-				     &next0, b0);
+		  vnet_feature_next (&next0, b0);
 		}
 	      vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 					       n_left_to_next, bi0, next0);