net: fix network drivers ndo_start_xmit() return values (part 7)

Fix up ATM drivers that return an errno value to qdisc_restart(), causing
qdisc_restart() to print a warning an requeue/retransmit the skb.

- lec: condition can only be remedied by userspace, until that retransmissions

Compile tested only.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/atm/lec.c b/net/atm/lec.c
index 75b9d59..ff2e594 100644
--- a/net/atm/lec.c
+++ b/net/atm/lec.c
@@ -270,7 +270,8 @@
 		printk("%s:No lecd attached\n", dev->name);
 		dev->stats.tx_errors++;
 		netif_stop_queue(dev);
-		return -EUNATCH;
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
 	}
 
 	pr_debug("skbuff head:%lx data:%lx tail:%lx end:%lx\n",