bonding: graph node running after bond-input in feature arc may crash

In bond RX quad loop, when all packets within the frame have the same incoming
interface, we cannot skip calling bond_update_next because that function calls
vnet_feature_next() to update the b->current_config_index. The next node needs
the correct b->current_config_index to work with.

Type: fix

Signed-off-by: Steven Luong <sluong@cisco.com>
Change-Id: I3d8b3d4e0f95490f406fae7638f0c43c301ce664
diff --git a/src/vnet/feature/feature.h b/src/vnet/feature/feature.h
index 2d1569b..6e34018 100644
--- a/src/vnet/feature/feature.h
+++ b/src/vnet/feature/feature.h
@@ -219,6 +219,13 @@
 			     void *feature_config,
 			     u32 n_feature_config_bytes);
 
+static_always_inline u32
+vnet_get_feature_count (u8 arc, u32 sw_if_index)
+{
+  vnet_feature_main_t *fm = &feature_main;
+  return (fm->feature_count_by_sw_if_index[arc][sw_if_index]);
+}
+
 static inline vnet_feature_config_main_t *
 vnet_get_feature_arc_config_main (u8 arc_index)
 {