message: storage/cache: make do_fetch_chunk error more verbose
diff: @@ -219,7 +219,8 @@ pub trait BlobCache: Send + Sync {
  || ((!self.is_stargz() && d_size as u64 > RAFS_MAX_CHUNK_SIZE)
  || (self.is_stargz() && d_size > 4 << 20))
  {
  - return Err(eio!("chunks to read_chunks() is invalid"));
  + return Err(eio!(format!("chunks to read_chunks() is invalid, offset {} last {} blob_offset {} d_size {}",
  + offset, last, blob_offset, d_size)));
  }
  let offset_merged = (offset - blob_offset) as usize;
  