message: nydus-image: disable validation when creating images
  It's too hard to maintain the validation functionality when creating
  images. On the other hand, user may execute `nydus-image check` to
  validate images. So disable image validation when creating images.
diff: @@ -302,6 +302,7 @@ fn prepare_cmd_args(bti_string: &'static str) -> App {
  Arg::new("disable-check")
  .long("disable-check")
  .help("Disable RAFS metadata validation after build")
  + .hide(true)
  .action(ArgAction::SetTrue)
  .required(false)
  )
  @@ -848,13 +849,6 @@ impl Command {
  event_tracer!("euid", "{}", geteuid());
  event_tracer!("egid", "{}", getegid());
  - // Validate output bootstrap file
  - if !blob_inline_meta {
  - if let Some(ArtifactStorage::SingleFile(p)) = &bootstrap_mgr.bootstrap_storage {
  - Self::validate_image(matches, p, config).context("failed to validate bootstrap")?;
  - }
  - }
  -
  info!("successfully built RAFS filesystem: \n{}", build_output);
  OutputSerializer::dump(matches, build_output, build_info)
  }
  @@ -1226,26 +1220,6 @@ impl Command {
  }
  }
  - fn validate_image(
  - matches: &clap::ArgMatches,
  - bootstrap_path: &Path,
  - config: Arc<ConfigV2>,
  - ) -> Result<()> {
  - if !matches.get_flag("disable-check") {
  - let mut validator = Validator::new(bootstrap_path, config)?;
  - timing_tracer!(
  - {
  - validator
  - .check(false)
  - .context("failed to validate bootstrap")
  - },
  - "validate_bootstrap"
  - )?;
  - }
  -
  - Ok(())
  - }
  -
  fn get_chunk_size(matches: &ArgMatches, ty: ConversionType) -> Result<u32> {
  match matches.get_one::<String>("chunk-size") {
  None => {
  