to allow to register an array of drivers

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Check link status on eth device open time and then periodically
every 5 seconds.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Adapt phylib from linux

switch all the driver to it
reimplement mii bus

This will allow to have
 - phy drivers
 - to only connect the phy at then opening of the device
 - if the phy is not ready or not up fail on open

Same behaviour as in linux and will allow to share code and simplify porting.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>