r8169: remove unneeded call to __rtl8169_set_features in rtl_open

RxChkSum and RxVlan aren't touched outside __rtl8169_set_features
(except in probe), so they are always in sync with dev->features.
And the RxConfig flags are set in rtl_set_rx_mode() which is
called via dev_set_rx_mode() from __dev_open().
Therefore we can safely remove this call.

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