Serial console over USB to see boot messages

**Is your feature request related to a problem? Please describe.**

We would like to have a serial console over USB to see boot messages

**Describe the solution you'd like**

Press Shift-V during early boot, and the output will be directed to a serial console over USB.

The lua code needs to go here:

https://github.com/helloSystem/ISO/blob/ae0880e6889ee568194b8c60135a442787b04bab/overlays/boot/boot/lua/local.lua#L82

Somehow we don't succeed in loading the needed kernel modules in this way yet. Probably it needs to be done differently?

**Describe alternatives you've considered**

Typing commands at the bootloader prompt

**Additional context**

Reference:

* https://github.com/helloSystem/ISO/issues/505#issuecomment-1704003861