net: gro: GRO_MERGED_FREE consumes packets

As part of GRO processing, merged skbs should be consumed, not freed, to
not confuse dropwatch/drop_monitor.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/dev.c

@@ -3542,10 +3542,13 @@ gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
 		break;
 
 	case GRO_DROP:
-	case GRO_MERGED_FREE:
 		kfree_skb(skb);
 		break;
 
+	case GRO_MERGED_FREE:
+		consume_skb(skb);
+		break;
+
 	case GRO_HELD:
 	case GRO_MERGED:
 		break;