ENGR00275469 net:fec: move devm_* and of_* apis to probe function

ENGR00275469 net:fec: move devm_* and of_* apis to probe function

fec_reset_phy() function is called in fec_enet_open(). And
fec_reset_phy() call of_get_named_gpio() and devm_gpio_request_one()
apis, which makes no sense since the two apis do something that
should only be done at .probe() time.

So move two functions into fec_probe() and only leave gpio_set_value()
and msleep() calls in fec_reset_phy(). And remove fec_free_reset_gpio()
function.

Signed-off-by: Fugang Duan  <B38611@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>