net: phy: icplus: don't set APS_EN bit on IP101G

This bit is reserved as 'always-write-1'. While this is not a particular
error, because we are only setting it, guard it by checking the model to
prevent errors in the future.

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