v0.0.1

Copy the .mpy into the CIRCUITPY drive's lib/, renamed to
lr2021.mpy.

One architecture only: xtensawin, for the ESP32-S3. This driver's
board is the Meshnology W12, and a native .mpy is machine code,
so there is nothing to offer for other CPUs.

The firmware must be built with CIRCUITPY_ENABLE_MPY_NATIVE=1, or
the import fails with "native code in .mpy unsupported".

The module is FLRC arithmetic. Driving the radio is still done from
Python -- see examples/flrc_link/.

Full Changelog: https://github.com/fede2cr/cpy-lr2021/commits/v0.0.1