Still see some USB issues apparently caused by delays loading wifi
firmware. cyw43_delay_ms is used to wait in the driver, so we should call
the event hook in there.
Fixes#8963.
This includes:
- Configuration file for the cyw43-driver.
- Integration of cyw43-driver into the build, using lwIP.
- Enhancements to machine.Pin to support extension IO pins provided by the
CYW43xx.
- More mp-hal pin helper functions.
- mp_hal_get_mac_ascii MAC address helper function.
- Addition of rp2.country() function to set the country code.
A board can enable this driver by setting MICROPY_PY_NETWORK_CYW43 in their
cmake snippet.
Work done in collaboration with Graham Sanderson and Peter Harper.
Signed-off-by: Damien George <damien@micropython.org>
