The simple-cam application has a check to ensure that at least one camera is present before attempting to access the first camera, to avoid a crash. Update the application developer's guide to match this behaviour. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>