Hyundai CAN: gear shifter and accelerator pedal signals for FCEV

[sunnyhaibin]

Checklist

• added entry to CarInfo in selfdrive/car/*/values.py and ran selfdrive/car/docs.py to generate new docs
• test route added to routes.py
• route with stock system: a74afe0cf708748f|2023-09-02--19-56-27
• route with openpilot: a74afe0cf708748f|2023-09-10--11-18-49
• harness Type: Hyundai H
• architecture: CAN

Link to all physical parts during installation

• comma 3X
• car harness kit
  • Hyundai H

Requires

• Hyundai: Car Port for Nexo 2021 panda#1637

Thanks to community 2021 Hyundai Nexo owner SimonYang402.

Defines gear shifter and accelerator pedal signals for FCEV cars.

Gear Shifter		Accelerator Pedal
a74afe0cf708748f|2023-09-04--18-31-39		a74afe0cf708748f|2023-09-05--19-40-54

Supersedes commaai/openpilot#29771

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