Implement native posix or qemu support

[jalgroy]

Would be nice to be able to run multiple instances of the mesh node on a host machine

Some useful links:

• Potential hardware simultaion: https://babblesim.github.io/ (Add support for NRF53 and DPPI BabbleSim/ext_NRF52_hw_models#18)
• Native posix support in zephyr: https://docs.zephyrproject.org/latest/boards/posix/native_posix/doc/index.html