net: lapb: Use list_for_each_entry() to simplify code in lapb_iface.c

Convert list_for_each() to list_for_each_entry() where
applicable. This simplifies the code.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/lapb/lapb_iface.c

@@ -80,11 +80,9 @@ static void __lapb_insert_cb(struct lapb_cb *lapb)
 
 static struct lapb_cb *__lapb_devtostruct(struct net_device *dev)
 {
-	struct list_head *entry;
 	struct lapb_cb *lapb, *use = NULL;
 
-	list_for_each(entry, &lapb_list) {
-		lapb = list_entry(entry, struct lapb_cb, node);
+	list_for_each_entry(lapb, &lapb_list, node) {
 		if (lapb->dev == dev) {
 			use = lapb;
 			break;