[NET]: ethtool ops are the only way

During the transition to the ethtool_ops way of doing things, we supported
calling the device's ->do_ioctl method to allow unconverted drivers to
continue working.  Those days are long behind us, all in-tree drivers
use the ethtool_ops way, and so we no longer need to support this.

The bonding driver is the biggest beneficiary of this; it no longer
needs to call ioctl() as a fallback if ethtool_ops aren't supported.

Also put a proper copyright statement on ethtool.c.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/8021q/vlan_dev.c

@@ -668,9 +668,6 @@ int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 		if (real_dev->do_ioctl && netif_device_present(real_dev))
 			err = real_dev->do_ioctl(real_dev, &ifrr, cmd);
 		break;
-
-	case SIOCETHTOOL:
-		err = dev_ethtool(&ifrr);
 	}
 
 	if (!err)