When both the Marvell MV643XX ethernet driver and the Orion MDIO driver
are compiled as modules, the ethernet driver may be probed before the
MDIO driver.  Let mv643xx_eth_probe() return EPROBE_DEFER in this case,
i.e. when it cannot find the PHY.
Signed-off-by: Simon Baatz <gmbnomis@gmail.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>