|SUCCESS| [v2] argparse: support range step for corelist parsing

[dpdklab at iol.unh.edu]

Test-Label: ai-code-review
Test-Status: SUCCESS
https://dpdk.org/patch/171628

_AI Code Review_

=== Patch Review: series.patch (via Claude) ===
Review date: 2026-10-19

# DPDK Patch Review

## Errors

None identified.

## Warnings

None identified.

## Info

### Test Coverage

The test cases are comprehensive, covering valid and invalid step syntax patterns. Good coverage of edge cases including:
- Step larger than range (`1-5:10`)
- Reverse ranges with step (`10-5:2`)
- Mixed format with multiple stepped ranges
- Invalid cases (zero step, negative step, incomplete syntax)

### Documentation

The documentation updates in `argparse_lib.rst` and release notes clearly explain the new feature with examples. The release note appropriately describes the use case (avoiding sibling cores on SMT systems).

### Code Quality

The implementation correctly handles:
- Step validation (rejects zero, negative, and out-of-range values)
- Range normalization (reverses `min > max` before applying step)
- Mixed format with stepped and non-stepped ranges
- State reset after each range completion

The loop iteration `for (; min <= max; min += step)` correctly implements strided enumeration.

### Variable Scope

The variables `is_step`, `step`, and `max` are moved to function scope to maintain state across loop iterations. This is correct for the multi-token parsing logic, though it slightly increases function complexity. The state is properly reset after each complete range is processed.

Review-Result: CLEAN