rtnl: export physical port id via RT netlink

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Narendra K <narendra_k@dell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/if_link.h

@@ -143,6 +143,7 @@ enum {
 	IFLA_NUM_TX_QUEUES,
 	IFLA_NUM_RX_QUEUES,
 	IFLA_CARRIER,
+	IFLA_PHYS_PORT_ID,
 	__IFLA_MAX
 };