[media] v4l2-async: call registered_async after subdev registration

V4L2 sub-devices might need to do initialization that depends on being
registered with a V4L2 device. As an example, sub-devices with Media
Controller support may need to register entities and create pad links.

Execute the registered_async callback after the sub-device has been
registered with the V4L2 device so the driver can do any needed init.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/v4l2-core/v4l2-async.c

@@ -119,6 +119,13 @@ static int v4l2_async_test_notify(struct v4l2_async_notifier *notifier,
 		return ret;
 	}
 
+	ret = v4l2_subdev_call(sd, core, registered_async);
+	if (ret < 0) {
+		if (notifier->unbind)
+			notifier->unbind(notifier, sd, asd);
+		return ret;
+	}
+
 	if (list_empty(&notifier->waiting) && notifier->complete)
 		return notifier->complete(notifier);