net: phy: realtek: add delay to resume path of certain internal PHY's

Internal PHY's from RTL8168h up may not be instantly ready after calling
genphy_resume(). So far r8169 network driver adds the needed delay, but
better handle this in the PHY driver. The network driver may miss other
places where the PHY is resumed.

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>