Empty dict raises an exception when exporting quantized MPT models because when `state_dict = {}`, the HF loading pipeline will try to initialize the model by calling `_init_weights` for each module. However, for MPT models, this function is not defined and will therefore raise an exception.

@neuralmagic/machine-learning on a side note, I am not really sure what this function is supposed to do. According to the code it will return either `None` (for pruned model) or `{}` (for quantized model), but never the actual loaded `state_dict` as mentioned in the docstring. We might want to rethink whether we need to refactor the function and its usage, or at least to update the docstring?