net: Add support for SMSC LAN9530, LAN9730 and LAN89530

This patch adds support for SMSC's LAN9530, LAN9730 and LAN89530 USB
ethernet controllers to the existing smsc95xx driver by adding
their new USB VID/PID pairs.

Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com>
Signed-off-by: David S. Miller <davem@davemloft.net>