net/8021q: Implement Multiple VLAN Registration Protocol (MVRP)

Initial implementation of the Multiple VLAN Registration Protocol
(MVRP) from IEEE 802.1Q-2011, based on the existing implementation
of the GARP VLAN Registration Protocol (GVRP).

Signed-off-by: David Ward <david.ward@ll.mit.edu>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/if_ether.h

@@ -83,6 +83,7 @@
 #define ETH_P_802_EX1	0x88B5		/* 802.1 Local Experimental 1.  */
 #define ETH_P_TIPC	0x88CA		/* TIPC 			*/
 #define ETH_P_8021AH	0x88E7          /* 802.1ah Backbone Service Tag */
+#define ETH_P_MVRP	0x88F5          /* 802.1Q MVRP                  */
 #define ETH_P_1588	0x88F7		/* IEEE 1588 Timesync */
 #define ETH_P_FCOE	0x8906		/* Fibre Channel over Ethernet  */
 #define ETH_P_TDLS	0x890D          /* TDLS */

include/uapi/linux/if_vlan.h

@@ -34,6 +34,7 @@ enum vlan_flags {
 	VLAN_FLAG_REORDER_HDR	= 0x1,
 	VLAN_FLAG_GVRP		= 0x2,
 	VLAN_FLAG_LOOSE_BINDING	= 0x4,
+	VLAN_FLAG_MVRP		= 0x8,
 };
 
 enum vlan_name_types {