Fix passing kwargs in PytorchHubMixin

[Wauplin]

Fix breaking change introduced in #2058.

If __init__ expects a **kwargs parameter, we should pass the config to it. However if it expects something like **croco_kwargs, let's not forward it since config is most likely not expected by the underlying class that will receive the config.

This will fix integration like the dust3r one (see here + slack thread -private-).

cc @NielsRogge @not-lain

[HuggingFaceDocBuilderDev]

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