The ControlList::update() method is unused. While it is meant to fulfil a need of applications, having no user means that it is most probably not correctly designed. Remove the method, we will add it back later if needed. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>