add quant_state to state_dict

[yuchengliu1]

Fix the failure happened when the module's name mismatches the state dict keys if a layer rewrites the _save_to_state_dict function.

[jiqing-feng]

I don't know if it's a robust fix because quant_state is BNB-specific. Besides, I'd like to know why we wrap state_dict in ipex. Thanks!

[yuchengliu1]

We need modify the static_dict according to the wrapper of parameter. So we recursively find the parameter from model by the key of original static_dict. BNB hook the recursive process when generating the static_dict. The different of recursive process between IPEX and BNB cause the failure.

[jiqing-feng]

As we discussed offline. The BNB rewrite the _save_to_state_dict func so the quant_state parameter can be accessed. IPEX need same modification to read quant_state parameter.