fix loss normalization for ddp training

haoneng.lhn

2023-12-08 ace42e5043be992c3a324fc637ba0594f10ad3b6

 funasr/layers/inversible_interface.py

@@ -11,4 +11,4 @@
        self, input: torch.Tensor, input_lengths: torch.Tensor = None
    ) -> Tuple[torch.Tensor, torch.Tensor]:
        # return output, output_lengths
        raise NotImplementedError
        raise NotImplementedError