devlink: add warning in case driver does not set port type

Prevent misbehavior of drivers who would not set port type for longer
period of time. Drivers should always set port type. Do WARN if that
happens.

Note that it is perfectly fine to temporarily not have the type set,
during initialization and port type change.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/devlink.h b/include/net/devlink.h
index 1c4adfb..151eb93 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -17,6 +17,7 @@
 #include <linux/list.h>
 #include <linux/netdevice.h>
 #include <linux/spinlock.h>
+#include <linux/workqueue.h>
 #include <net/net_namespace.h>
 #include <uapi/linux/devlink.h>
 
@@ -64,6 +65,7 @@ struct devlink_port {
 	enum devlink_port_type desired_type;
 	void *type_dev;
 	struct devlink_port_attrs attrs;
+	struct delayed_work type_warn_dw;
 };
 
 struct devlink_sb_pool_info {