Update base_llm.py

[seanxuu]

Increase code flexibility and backward compatibility

[Harold-lkk]

We do not want to support **kwargs in BaseModel, for it wont raise error when wrong init parameter

[seanxuu]

We do not want to support **kwargs in BaseModel, for it wont raise error when wrong init parameter

In fact, I ran into an issue where if I tried to pass in device_map='auto', it reported an error. But this is a useful parameter in AutoModelForCausalLM.from_pretrained. If there any other solution?

[Harold-lkk]

we have model_kwargs for HFTransformer model, which will be passed to AutoModelForCausalLM