Use NVFP4 Marlin for CompressedTensorsW4A16Fp4

[mgoin]

Update CT FP4 weight only path to use the nvfp4 dense marlin kernels from #17687 and remove slow emulation

[github-actions]

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[dsikka]

Evals - Using CT with NVFp4A16 for a LLama 3.1 8b:

vllm (pretrained=nm-testing/Llama-3.1-8B-Instruct-FP4-Weight,add_bos_token=True), gen_kwargs: (None), limit: None, num_fewshot: None, batch_size: 100
|Tasks|Version|     Filter     |n-shot|  Metric   |   |Value |   |Stderr|
|-----|------:|----------------|-----:|-----------|---|-----:|---|-----:|
|gsm8k|      3|flexible-extract|     5|exact_match|↑  |0.7301|±  |0.0122|
|     |       |strict-match    |     5|exact_match|↑  |0.6376|±  |0.0132|

[tlrmchlsmth]

Nice