Move generic PyTorch utils function from modeling_utils.py to pytorch_utils
# 🚀 Feature request

> Since we're creating a new module file, can we maybe move some other functions there? Like the no_init_weight context manager, and:
> 
> all pruning stuff
> apply_chunking_to_forward
> get_parameter_device
> get_parameter_dtype
> so that the modeling utils file stays focused on PreTrainedModel and the layers it defines?

Taken from comment here: https://github.com/huggingface/transformers/pull/15498#pullrequestreview-874783288

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may I work on this issue?<|||||>Yes please :-)<|||||>Great job @davidegavio ! Really nice clean-up :-)