feat: allow loading models without a smash config

[sharpenb]

Description

This PR enables to load any diffusers and transformers models even if they do not have smash configs. This is useful for benchmarking of all models regardless if they are wrapped or not with Pruna.

Related Issue

Fixes #(issue number)

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Additional Notes

[SaboniAmine]

LGTM!

[gsprochette]

Looks good, a single iteration should do it :)

• I would recommend renaming the PR to something in the line of feat: allow loading models without a smash config.
• If we decide to add a device_map argument in the loading functions, that can be done in an other PR

[gsprochette]

LGTM, thanks for doing all the changes :)