[Tracing] Copy HFTracer to support latest transformers (#1989)

## Background ##
* huggingface/transformers#41683 remove some fx
tracing utilities used by LLM Compressor's sequential pipeline
capabilities

## Purpose ##
* Allow LLM Compressor to support latest transformers

## Changes ##
* Copied `src/transformers/utils/fx.py` (with copyright)
* Use `trust_remote_code` for trace testing (the old deepseek model
definitions are not supported with the latest transformers

## Testing ##
* Used `test_models` to test that all models can still trace with
transformers main
* Quantized llama 8B e2e and confirmed sane outputs with transformers
main

---------

Signed-off-by: Kyle Sayers <[email protected]>

Author: kylesayrs

src/llmcompressor/pipelines/sequential/helpers.py

@@ -19,10 +19,10 @@
 from torch.nn import Module
 from transformers import PreTrainedModel
 from transformers.configuration_utils import PretrainedConfig
-from transformers.utils.fx import HFTracer
 
 from llmcompressor.modifiers import Modifier
 from llmcompressor.modifiers.utils.hooks import HooksMixin
+from llmcompressor.pipelines.sequential.transformers_helpers import HFTracer
 from llmcompressor.utils.helpers import calibration_forward_context, patch_attr
 from llmcompressor.utils.pytorch.module import get_no_split_params