net: remove MTU limits on a few ether_setup callers

These few drivers call ether_setup(), but have no ndo_change_mtu, and thus
were overlooked for changes to MTU range checking behavior. They
previously had no range checks, so for feature-parity, set their min_mtu
to 0 and max_mtu to ETH_MAX_MTU (65535), instead of the 68 and 1500
inherited from the ether_setup() changes. Fine-tuning can come after we get
back to full feature-parity here.

CC: [e-mail]
Reported-by: Asbjoern Sloth Toennesen <[e-mail]>
CC: Asbjoern Sloth Toennesen <[e-mail]>
CC: R Parameswaran <[e-mail]>
Signed-off-by: Jarod Wilson <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/atm/br2684.c

···
 	netdev->hard_header_len = sizeof(llc_oui_ipv4); /* worst case */
 	netdev->netdev_ops = &br2684_netdev_ops_routed;
 	netdev->addr_len = 0;
-	netdev->mtu = 1500;
+	netdev->mtu = ETH_DATA_LEN;
+	netdev->min_mtu = 0;
+	netdev->max_mtu = ETH_MAX_MTU;
 	netdev->type = ARPHRD_PPP;
 	netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 	netdev->tx_queue_len = 100;

net/bluetooth/bnep/netdev.c

···
 	dev->addr_len = ETH_ALEN;
 
 	ether_setup(dev);
+	dev->min_mtu = 0;
+	dev->max_mtu = ETH_MAX_MTU;
 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
 	dev->netdev_ops = &bnep_netdev_ops;
 

net/dsa/slave.c

···
 	slave_dev->priv_flags |= IFF_NO_QUEUE;
 	slave_dev->netdev_ops = &dsa_slave_netdev_ops;
 	slave_dev->switchdev_ops = &dsa_slave_switchdev_ops;
+	slave_dev->min_mtu = 0;
+	slave_dev->max_mtu = ETH_MAX_MTU;
 	SET_NETDEV_DEVTYPE(slave_dev, &dsa_type);
 
 	netdev_for_each_tx_queue(slave_dev, dsa_slave_set_lockdep_class_one,

net/irda/irlan/irlan_eth.c

···
 
 	dev->netdev_ops		= &irlan_eth_netdev_ops;
 	dev->destructor		= free_netdev;
-
+	dev->min_mtu		= 0;
+	dev->max_mtu		= ETH_MAX_MTU;
 
 	/*
 	 * Lets do all queueing in IrTTP instead of this device driver.

net/l2tp/l2tp_eth.c

···
 		session->mtu = dev->mtu - session->hdr_len;
 	dev->mtu = session->mtu;
 	dev->needed_headroom += session->hdr_len;
+	dev->min_mtu = 0;
+	dev->max_mtu = ETH_MAX_MTU;
 
 	priv = netdev_priv(dev);
 	priv->dev = dev;