message: nydus-image/inspect: print hunman-readable rafs flags
  So it is more friendly to end users.
diff: @@ -18,6 +18,7 @@ use rafs::metadata::layout::v5::{
  RafsV5BlobTable, RafsV5ChunkInfo, RafsV5ExtBlobTable, RafsV5Inode, RafsV5InodeTable,
  RafsV5PrefetchTable, RafsV5SuperBlock, RafsV5XAttrsTable,
  };
  +use rafs::metadata::RafsSuperFlags;
  use rafs::{RafsIoRead, RafsIoReader};
  pub(crate) struct RafsInspector {
  @@ -569,7 +570,7 @@ Blocks: {blocks}"#,
  Flags: {flags}"#,
  version = sb.version(),
  inodes_count = sb.inodes_count(),
  - flags = sb.flags()
  + flags = RafsSuperFlags::from_bits(sb.flags()).unwrap()
  );
  None
  