r8169: restrict rtl_is_8168evl_up to RTL8168 chip versions

Extend helper rtl_is_8168evl_up to properly work once we add
mac version numbers >51 for RTL8125.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index bf00c3d..e9d900c 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -730,7 +730,8 @@ static void rtl_tx_performance_tweak(struct rtl8169_private *tp, u16 force)
 static bool rtl_is_8168evl_up(struct rtl8169_private *tp)
 {
 	return tp->mac_version >= RTL_GIGA_MAC_VER_34 &&
-	       tp->mac_version != RTL_GIGA_MAC_VER_39;
+	       tp->mac_version != RTL_GIGA_MAC_VER_39 &&
+	       tp->mac_version <= RTL_GIGA_MAC_VER_51;
 }
 
 static bool rtl_supports_eee(struct rtl8169_private *tp)