libcamera: camera: Reset request sequence number on stop/start

We now have V4L2VideoDevice ensuring that sensor sequence numbers
start from zero [1], and we desire that these should match the Request
sequence number as well.

[1] 1c9dc0fd89 ("libcamera: v4l2_videodevice: Identify non-zero stream starts")

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/libcamera/pipeline_handler.cpp

@@ -312,6 +312,8 @@ void PipelineHandler::stop(Camera *camera)
 	/* Make sure no requests are pending. */
 	Camera::Private *data = camera->_d();
 	ASSERT(data->queuedRequests_.empty());
+
+	data->requestSequence_ = 0;
 }
 
 /**