rtnl: expose carrier value with possibility to set it

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 60f3b6b..c4edfe1 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -142,6 +142,7 @@
 #define IFLA_PROMISCUITY IFLA_PROMISCUITY
 	IFLA_NUM_TX_QUEUES,
 	IFLA_NUM_RX_QUEUES,
+	IFLA_CARRIER,
 	__IFLA_MAX
 };