al_eth: improve TCP LRO

Use the appropriate function to flush correctly all entries. The old
code does not remove the element from the hash table, only from the
active queue.

Reviewed by:		Peter Lei, rscheff
MFC after:		1 week
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D46434

sys/dev/al_eth/al_eth.c

@@ -1580,7 +1580,6 @@ al_eth_rx_recv_work(void *arg, int pending)
 {
 	struct al_eth_ring *rx_ring = arg;
 	struct mbuf *mbuf;
-	struct lro_entry *queued;
 	unsigned int qid = rx_ring->ring_id;
 	struct al_eth_pkt *hal_pkt = &rx_ring->hal_pkt;
 	uint16_t next_to_clean = rx_ring->next_to_clean;
@@ -1671,10 +1670,7 @@ al_eth_rx_recv_work(void *arg, int pending)
 		    "%s: not filling rx queue %d\n", __func__, qid);
 	}
 
-	while (((queued = LIST_FIRST(&rx_ring->lro.lro_active)) != NULL)) {
-		LIST_REMOVE(queued, next);
-		tcp_lro_flush(&rx_ring->lro, queued);
-	}
+	tcp_lro_flush_all(&rx_ring->lro);
 
 	if (napi != 0) {
 		rx_ring->enqueue_is_running = 0;