Change the chunk_iter function to handle
Author: Narsil
Pull request: yes

the subtle cases where the last chunk gets ignored since all the
data is in the `left_strided` data.

We need to remove the right striding on the previous item.


# What does this PR do?

Change the chunk_iter function to handle

the subtle cases where the last chunk gets ignored since all the
data is in the `left_strided` data.

We need to remove the right striding on the previous item.


Fixes https://github.com/huggingface/transformers/issues/16671


@LysandreJik @patrickvonplaten

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Fixes # (issue)


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Comments:
Very nice - thanks for fixing it!

@sgugger - I think the build doc failing test is unrelated here no?

Yes, will look into that.