fix loss normalization for ddp training

haoneng.lhn

2023-12-08 ace42e5043be992c3a324fc637ba0594f10ad3b6

 funasr/models/frontend/abs_frontend.py

@@ -14,4 +14,4 @@
    def forward(
        self, input: torch.Tensor, input_lengths: torch.Tensor
    ) -> Tuple[torch.Tensor, torch.Tensor]:
        raise NotImplementedError
        raise NotImplementedError