message: storage: change error type if meta file is not found
  ENOENT would be more suggestive.
diff: @@ -603,7 +603,7 @@ impl BlobObject for FileCacheEntry {
  }
  fn fetch_range_compressed(&self, offset: u64, size: u64) -> Result<()> {
  - let meta = self.meta.as_ref().ok_or_else(|| einval!())?;
  + let meta = self.meta.as_ref().ok_or_else(|| enoent!())?;
  let meta = meta.get_blob_meta().ok_or_else(|| einval!())?;
  let mut chunks = meta.get_chunks_compressed(offset, size, self.prefetch_batch_size())?;
  if let Some(meta) = self.get_blob_meta_info()? {
  