linux-phytec-ti

net: davinci_mdio: add GPIO reset logic

Some boards [1] leave the PHYs at an invalid state
during system power-up or reset thus causing unreliability
issues with the PHY like not being detected by the mdio bus
or link not functional. To work around these boards have
a GPIO connected to the PHY's reset pin.

Implement GPIO reset handling for such cases.

[1] - am572x-idk, am571x-idk, a437x-idk.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>