net: phy: micrel: set soft_reset callback to genphy_soft_reset for KSZ9031

So far genphy_soft_reset was used automatically if the PHY driver
didn't implement the soft_reset callback. This changed with the
mentioned commit and broke KSZ9031. To fix this configure the
KSZ9031 PHY driver to use genphy_soft_reset.

Fixes: 6e2d85ec ("net: phy: Stop with excessive soft reset")
Reported-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Tested-by: NTony Lindgren <tony@atomide.com>
Tested-by: NSekhar Nori <nsekhar@ti.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/phy/micrel.c

@@ -1070,6 +1070,7 @@ static struct phy_driver ksphy_driver[] = {
 	.driver_data	= &ksz9021_type,
 	.probe		= kszphy_probe,
 	.config_init	= ksz9031_config_init,
+	.soft_reset	= genphy_soft_reset,
 	.read_status	= ksz9031_read_status,
 	.ack_interrupt	= kszphy_ack_interrupt,
 	.config_intr	= kszphy_config_intr,