r8169: fix failing WoL

Th referenced change added an extra hw reset to rtl8169_net_suspend()
what makes WoL fail on few chip versions. Therefore skip the extra
reset if we're going down and WoL is enabled.
In rtl_shutdown() rtl8169_hw_reset() is called by rtl8169_net_suspend()
already if needed, therefore avoid issues issue by removing the extra
call. The fix was tested on a system with RTL8168g.

Meanwhile rtl8169_hw_reset() does more than a hw reset and should be
renamed. But that's net-next material.

Fixes: 8ac8e8c6

 ("r8169: make rtl8169_down central chip quiesce function")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>