ag71xx: Slightly simplify 'ag71xx_rx_packets()'

There is no need to use 'list_for_each_entry_safe' here, as nothing is
removed from the list in the 'for' loop.
Use 'list_for_each_entry' instead, it is slightly less verbose.

Signed-off-by: Christophe JAILLET <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/15435
Link: https://github.com/openwrt/openwrt/pull/15435
Signed-off-by: Christian Marangi <[email protected]>

target/linux/ath79/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c

@@ -1319,7 +1319,6 @@ static int ag71xx_rx_packets(struct ag71xx *ag, int limit)
 	int ring_mask = BIT(ring->order) - 1;
 	int ring_size = BIT(ring->order);
 	struct list_head rx_list;
-	struct sk_buff *next;
 	struct sk_buff *skb;
 	int done = 0;
 
@@ -1379,7 +1378,7 @@ next:
 
 	ag71xx_ring_rx_refill(ag);
 
-	list_for_each_entry_safe(skb, next, &rx_list, list)
+	list_for_each_entry(skb, &rx_list, list)
 		skb->protocol = eth_type_trans(skb, dev);
 	netif_receive_skb_list(&rx_list);