net: Fix typo in netdev_intersect_features

Obviously need to 'or in NETIF_F_IP_CSUM and NETIF_F_IPV6_CSUM.

Fixes: c8cd0989bd ("net: Eliminate NETIF_F_GEN_CSUM and NETIF_F_V[46]_CSUM")
Reported-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -3873,9 +3873,9 @@ static inline netdev_features_t netdev_intersect_features(netdev_features_t f1,
 {
 	if ((f1 ^ f2) & NETIF_F_HW_CSUM) {
 		if (f1 & NETIF_F_HW_CSUM)
-			f1 |= (NETIF_F_IP_CSUM|NETIF_F_IP_CSUM);
+			f1 |= (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
 		else
-			f2 |= (NETIF_F_IP_CSUM|NETIF_F_IP_CSUM);
+			f2 |= (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
 	}
 
 	return f1 & f2;