…NVIDIA#1842)

Use the correct fields when parsing the NMX-C response in the
nvlink-info admin-cli command. Also, return an error if any of the
fields aren't parsed correctly instead of pushing a default value.

## Description
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## Type of Change
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- [ ] **Add** - New feature or capability
- [ ] **Change** - Changes in existing functionality  
- [x] **Fix** - Bug fixes
- [ ] **Remove** - Removed features or deprecated functionality
- [ ] **Internal** - Internal changes (refactoring, tests, docs, etc.)

## Related Issues (Optional)
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## Breaking Changes
- [ ] This PR contains breaking changes

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## Testing
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- [ ] Unit tests added/updated
- [ ] Integration tests added/updated  
- [x] Manual testing performed
- [ ] No testing required (docs, internal refactor, etc.)

## Additional Notes
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Signed-off-by: Thomas McRoberts <tmcroberts@nvidia.com>
Co-authored-by: rtamma-nv <rtamma@nvidia.com>