message: fix: not amplify io if next file in different blob
  BlobDevice only allow read in same blob, so if next ino
  in different blob should not amplify io.
  Refs:
diff: @@ -200,13 +200,21 @@ impl RafsSuper {
  break;
  }
  + if next_size == 0 {
  + continue;
  + }
  +
  let sz = std::cmp::min(window_size, next_size);
  let amplified_io_vec = ni.alloc_bio_vecs(0, sz as usize, false)?;
  debug_assert!(
  !amplified_io_vec.is_empty() && !amplified_io_vec[0].bi_vec.is_empty()
  );
  + if last_desc.has_same_blob(&amplified_io_vec[0]) {
  // caller should ensure that `window_base` won't overlap last chunk
  Self::merge_chunks_io(last_desc, &amplified_io_vec);
  + } else {
  + break;
  + }
  window_size -= sz;
  }
  } else {
  