net: bcmgenet: Remove excessive PHY reset

We are currently issuing multiple PHY resets during a suspend/resume,
first during bcmgenet_power_up() which does a hardware reset, then a
software reset by calling bcmgenet_mii_reset(). This is both unnecessary
and can take as long as 10ms per MDIO transactions while we re-apply
workarounds because we do not yet have MDIO interrupts enabled.

phy_resume() takes care of re-apply our workarounds in case we need any,
and bcmgenet_power_up() does a PHY hardware reset, all of this is more
than enough to guarantee that the PHY operates correctly.

Fixes: 1c1008c7

 ("net: bcmgenet: add main driver file")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>