Mazda: recognize CX-9 with swapped CX-5 EPS

[maxzzznz]

Summary

Recognize a 2021-2023 Mazda CX-9 with a supported 2022+ CX-5 EPS swap.

The existing EPS-swap logic already enables steer-to-zero after vehicle identification. However, firmware matching rejects a CX-9 when the reported EPS is KSD5-3210X-C-00, so it has no candidate and starts in dashcam mode unless the user manually forces CX-9.

This is particularly needed for export-market CX-9 firmware combinations, such as PXM7 (observed on a New Zealand CX-9), where the exact match rejects the swapped EPS and the fuzzy fallback does not have enough unique non-EPS firmware matches to identify the vehicle.

This adds the known swapped EPS firmware to the MAZDA_CX9_2021 fingerprint and tests the exact hybrid firmware set: CX-9 PCM, TCM, ABS, radar and camera firmware together with the CX-5 2022+ KSD5 EPS firmware.

Scope and safety

• Only expands the accepted EPS firmware list for the existing CX-9 2021-23 platform.
• Keeps the CX-9 vehicle parameters, radar, camera and longitudinal eligibility.
• Uses the existing EPS-specific logic for minimum steering speed and steering delay.
• Does not broaden fuzzy matching or change behavior for other Mazdas.

Test plan

• uv run --with pytest pytest -q opendbc/car/mazda/tests (100 passed)
• uv run --with ruff ruff check opendbc/car/mazda/fingerprints.py opendbc/car/mazda/tests/test_mazda_interface.py

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[zephleggett]

I think this PR should cover this for you :D
#5