Use the zero-copy variant of ByteStreamBuffer::read() to read packet headers and control entries. This enhances the performance of ControlList and ControlInfoMap deserialization. Deserialization of the actual ControlValue is untouched for now and will be optimized later. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.binghm@ideasonboard.com>