Removes all driver-specific SDA/SCL pin definitions and defaults.
Pin type is "uint" everywhere, but "PIN_UNUSED" is *int*_max for MicroPython compat. That's still a lot of pins!
Adds baudrate to the I2C class, and allows a driver (like Trackball) to check the baudrate is supported
* Add a common/pimoroni.hpp to list default pins for various add-ons
* Move the BG SPI Slot enum here for safe keeping
* Switch all GPIO pin references to "uint" to match Pico SDK and bring back PIN_UNUSED as UINT_MAX
This change removes file-relative include paths and adds the project root as a global include path.
* Project root added to CMakeLists.txt so that all targets can find includes
* Project root added micropython.cmake so that targets used by the MicroPython build can find includes
Note: pico-boilerplate projects must set this include path
Fixes paths that only resolve when the top-level directory is named "pimoroni-pico"
and is adjacent to the "micropython" directory when building a MicroPython release.
Phil Howard