[Issue 543] [Bug fix] Fix dynamic input quant for AWQ

[meenchen]

What does this PR do?

Type of change: Bug fix

Overview: Dynamic input quantizers, e.g., MXFP4, are not restored after AWQ. This PR fix the issue.

Usage

# Add a code snippet demonstrating how to use this

Testing

Tested with MXFP4, NVFP4, int4

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• Is this change backward compatible?: Yes/No
• Did you write any new necessary tests?: Yes/No
• Did you add or update any necessary documentation?: Yes/No
• Did you update Changelog?: Yes/No

Additional Information

[codecov]

Codecov Report

❌ Patch coverage is 88.88889% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 74.69%. Comparing base (3350b0a) to head (b24803e).

Files with missing lines	Patch %	Lines
modelopt/torch/quantization/model_calib.py	88.88%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #726      +/-   ##
==========================================
- Coverage   74.69%   74.69%   -0.01%     
==========================================
  Files         192      192              
  Lines       18946    18948       +2     
==========================================
+ Hits        14152    14153       +1     
- Misses       4794     4795       +1     

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