fix: add nvfp4_mse to autoquant choices (#1086)

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **New Features**
* Added support for the `nvfp4_mse` quantization format, enabling users
to select this format as an option for auto-quantization operations.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Signed-off-by: Fridah-nv <201670829+Fridah-nv@users.noreply.github.com>

Author: Fridah-nv

examples/llm_ptq/hf_ptq.py

@@ -273,6 +273,7 @@ def auto_quantize(
             "int4_awq",
             "nvfp4",
             "nvfp4_awq",
+            "nvfp4_mse",
             "w4a8_awq",
             "fp8_pb_wo",
             "w4a8_mxfp4_fp8",