This pull request, and the code behind it has been done by the amazing BugObliterator, known to the rest of us as our Siddharth…
What it represents is the biggest step in simplification and safety to the hardware setup of your vehicle.
I will let @sidbh explain the details, but the short version is, a predictable hardware setup for your vehicle that can be locked in.
Detect all the devices connected to your vehicle, then ensure the correct devices exist each time the vehicle starts.
It is also the missing part for true dual external CAN GPS and Mag on Ardupilot…