Fixed low_cpu_mem_usage issue #21039
Author: susnato
Pull request: yes

# What does this PR do?

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Fixes #21039

When using AutoModelForCausalLM.from_pretrained(..., low_cpu_mem_usage=True), for some models (with modified configs) are having problems loading their weights from the model_state_dict, this PR solves that.

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## Who can review?

Anyone in the community is free to review the PR once the tests have passed. 
@sgugger 

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Comments:
_The documentation is not available anymore as the PR was closed or merged._

Hi, @sgugger I solved the `check_code_quality` test but the `tests_torch` is still giving me error, I ran the whole test locally which was failing before(by checking from this [link](https://app.circleci.com/pipelines/github/huggingface/transformers/55152/workflows/03ea844b-2a40-4142-ab12-f7378c66ea5f/jobs/665222)) and also ran the specific test locally(tests/models/auto/test_modeling_auto.py) which was causing the error, both seem to run perfectly fine in my local system. (I also updated the environment before running them locally).

Would you please look in this matter? I can't seem to find the problem why tests are failing..... 

Hi, @sgugger I did all the changes you mentioned, and all the checks are successful now.