net: smsc95xx: add support for Microchip EVB-LAN8670-USB

This patch adds support for Microchip's EVB-LAN8670-USB 10BASE-T1S
ethernet device to the existing smsc95xx driver by adding the new
USB VID/PID pairs.

Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>