net: ethernet: slicoss: add slicoss gigabit ethernet driver

Add driver for Alacritech gigabit ethernet cards with SLIC (session-layer
interface control) technology. The driver provides basic support without
SLIC for the following devices:

- Mojave cards (single port PCI Gigabit) both copper and fiber
- Oasis cards (single and dual port PCI-x Gigabit) copper and fiber
- Kalahari cards (dual and quad port PCI-e Gigabit) copper and fiber

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>