add support for smc91x ethernet interface on zylonite

This patch adds LAN91C111 ethernet interface support for zylonite
(a.k.a Marvell's PXA3xx Development Platform) with smc91x driver.

It would be better if a patch would support zylonite along with all
other PXA boards with a single binary of smc91x driver, but it looks
quite difficult for the moment, so ugly #ifdef is still used here.

Signed-off-by: Aleksey Makarov <amakarov@ru.mvista.com>
Acked-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>