This removes the previous WiFi driver from drivers/cyw43 (but leaves behind
the BT driver), and makes the stm32 port (i.e. PYBD and Portenta) use the
new "lib/cyw43-driver" open-source driver already in use by the rp2 port.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Previously the interaction between the different layers of the Bluetooth
stack was different on each port and each stack. This commit defines
common interfaces between them and implements them for cyw43, btstack,
nimble, stm32, unix.
This makes a cleaner separation between the: driver, HCI UART and BT stack.
Also updated the naming to be more consistent (mp_bluetooth_hci_*).
Work done in collaboration with Jim Mussared aka @jimmo.
