netdevsim: implement support for devlink region and snapshots

Implement dummy region of size 32K and allow user to create snapshots
or random data using debugfs file trigger.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 95751a8..4c758c6 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -160,6 +160,7 @@ struct nsim_dev {
 	bool fw_update_status;
 	u32 max_macs;
 	bool test1;
+	struct devlink_region *dummy_region;
 };
 
 int nsim_dev_init(void);