In order to deserialise a ControlList, we will need to lookup ControlId instances based on their numerical ID. Generate a global map from the controls definitions to support such a lookup. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>