ethtool: allow flow-type ether without IP protocol field

Set IP protocol mask only when IP protocol field is set.
This will allow flow-type ether with vlan rule which don't have
protocol field to apply.

ethtool -N ens5f4 flow-type ether proto 0x8100 vlan 0x600\
m 0x1FFF action 3 loc 16
Signed-off-by: Vishal Kulkarni <vishal@chelsio.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ethtool/ioctl.c

@@ -3025,13 +3025,14 @@ ethtool_rx_flow_rule_create(const struct ethtool_rx_flow_spec_input *input)
 	case TCP_V4_FLOW:
 	case TCP_V6_FLOW:
 		match->key.basic.ip_proto = IPPROTO_TCP;
+		match->mask.basic.ip_proto = 0xff;
 		break;
 	case UDP_V4_FLOW:
 	case UDP_V6_FLOW:
 		match->key.basic.ip_proto = IPPROTO_UDP;
+		match->mask.basic.ip_proto = 0xff;
 		break;
 	}
-	match->mask.basic.ip_proto = 0xff;
 
 	match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_BASIC);
 	match->dissector.offset[FLOW_DISSECTOR_KEY_BASIC] =