MISRA compliance

[ZZ-Cat]

Currently, I am conducting some research and testing in a private project of mine that checks the code-base for MISRA compliance. Starting with MISRA C:2012, the goal here is to integrate MISRA compliance checking in with my existing Quality Control workflow, and CRSF for Arduino's code-base will be scanned for any MISRA C:2012 rule violations and the check will fail if one (or more) rules are violated in the code-base.

I am getting this into my pipeline, because it will increase the reliability of CRSF for Arduino's code-base tenfold - Especially when I implement #103, I feel like that can benefit from the extra reliability... because there is a very real potential for a 100% end-to-end DIY solution there, which means safety and reliability is paramount.

MISRA compliance is the next step in my series of Issues and Pull Requests for hardening CRSF for Arduino's code-base and supply chain. This does take priority above #103, because the Serial Transmitter Interface is the transmitter end of the control-and-telemetry link, with the Serial Receiver Interface at the receiver end. The Serial Transmitter Interface "completes the link", so to speak; and I want to make that link that bit more safer and more reliable.