<wip> Early draft of crossformer model
Fixes #22852 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_23130). All of your documentation changes will be reflected on that endpoint.<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md) are likely to be ignored.<|||||>Hi @raghavanone, thanks for opening this PR! 

The easiest, fastest and preferred way to add a new model is directly onto the hub: https://huggingface.co/docs/transformers/model_sharing

The bar for adding models into the transformers repo through a PR is a lot higher and will require all passing tests and approval from a maintainer. As such, adding this way will take a lot longer. <|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md) are likely to be ignored.