message: Simplify File::free_space()
diff: @@ -86,12 +86,7 @@ impl File {
  /// Returns the free space in the file in bytes (or 0 if the file handle is invalid).
  pub fn free_space(&self) -> u64 {
  - let freespace = h5lock!(H5Fget_freespace(self.id()));
  - if freespace < 0 {
  - 0
  - } else {
  - freespace as _
  - }
  + h5lock!(H5Fget_freespace(self.id())).max(0) as _
  }
  /// Returns true if the file was opened in a read-only mode.
  