net: phy: icplus: use the .soft_reset() of the phy-core

The PHY core already resets the PHY before .config_init() if a
.soft_reset() op is registered. Drop the open-coded ip1xx_reset().

Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>