[Lite] Save the model state_dict without _module or module by default?

[hiyyg]

In Lite, if I save model.state_dict(), it contains _module or even _module.module in ddp mode.
It will cause some problems, for example if a model is trained with multiple gpus and then test with a single gpu, the state_dict can not be loaded correctly.

Can we just save the state_dict without _module or module by default?