[media] v4l2-ctrl: Send change events to all fh for auto cluster slave controls

Otherwise the fh changing the master control won't get the inactive state
change event for the slave controls.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c
index c58c91b..2ece709 100644
--- a/drivers/media/video/v4l2-ctrls.c
+++ b/drivers/media/video/v4l2-ctrls.c
@@ -946,6 +946,7 @@
 			if (ctrl->cluster[0]->has_volatiles)
 				ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
 		}
+		fh = NULL;
 	}
 	if (changed || update_inactive) {
 		/* If a control was changed that was not one of the controls