r8169: don't read chip phy status register

Instead of accessing the PHYstatus register we can use the information
phylib stores in the phy_device structure.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>