net: phy: micrel: fix KSZ9477 PHY issues after suspend/resume

When the PHY is powered up after powered down most of the registers are
reset, so the PHY setup code needs to be done again.  In addition the
interrupt register will need to be setup again so that link status
indication works again.

Fixes: 26dd2974 ("net: phy: micrel: Move KSZ9477 errata fixes to PHY driver")
Signed-off-by: Tristram Ha <tristram.ha@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>