GPIO-Sim for development machines

[Trenton-Ruf]

We want to write and test code involving GPIO on our personal development machines.
In order to do that we need to simulate the GPIO to match the layout of the C3 board.

GPIO-SIM is a linux kernel module that will allow this. Simulated lines will be treated the same as real GPIO with libraries such as libgpiod that use the GPIO character device API.

[ryanpdx]

Please add a description of the task, idea, etc