net_sched: act_vlan: Add priority option

The current vlan push action supports only vid and protocol options.
Add priority option.

Example script that adds vlan push action with vid and
priority:

tc filter add dev veth0 protocol ip parent ffff: \
	   flower \
	   	indev veth0 \
	   action vlan push id 100 priority 5

Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/tc_act/tc_vlan.h b/include/net/tc_act/tc_vlan.h
index e29f52e..6b83588 100644
--- a/include/net/tc_act/tc_vlan.h
+++ b/include/net/tc_act/tc_vlan.h
@@ -20,6 +20,7 @@
 	int			tcfv_action;
 	u16			tcfv_push_vid;
 	__be16			tcfv_push_proto;
+	u8			tcfv_push_prio;
 };
 #define to_vlan(a) ((struct tcf_vlan *)a)