Take the unique pointer to the `Fence` object by rvalue reference
so that it is not destroyed if the function returns an error code
and does not take ownership of the unique pointer.
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Stefan Klug <stefan.klug@ideasonboard.com>