r8169: remove unused member features from struct

Member features of struct rtl8169_private isn't used any longer since
commit 6c6aa15f "r8169: improve interrupt handling", so remove it.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/r8169.c

@@ -832,8 +832,6 @@ struct rtl8169_private {
 		struct work_struct work;
 	} wk;
 
-	unsigned features;
-
 	struct mii_if_info mii;
 	dma_addr_t counters_phys_addr;
 	struct rtl8169_counters *counters;