r8169: load firmware for RTL8168fp/RTL8117

Load Realtek-provided firmware for RTL8168fp/RTL8117. Unlike the
firmware for other chip versions which is for the PHY, firmware for
RTL8168fp/RTL8117 is for the MAC.

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