staging: bcm2835_camera: Ensure all buffers are returned on disable

With the recent change to match MMAL and V4L2 buffers there
is a need to wait for all MMAL buffers to be returned during
stop_streaming.

Fixes: 9384167 "staging: bcm2835-camera: Remove V4L2/MMAL buffer remapping"
Signed-off-by: Dave Stevenson <[email protected]>

Author: 6by9

drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c

@@ -268,6 +268,8 @@ static void buffer_work_cb(struct work_struct *work)
 	if (!buffer->cmd)
 		atomic_dec(&msg_context->u.bulk.port->buffers_with_vpu);
 
+	atomic_dec(&msg_context->u.bulk.port->buffers_with_vpu);
+
 	msg_context->u.bulk.port->buffer_cb(msg_context->u.bulk.instance,
 					    msg_context->u.bulk.port,
 					    msg_context->u.bulk.status,