This is only a surface level refactor, some deeper refactoring would be
possible with (for example) the SDIO interface in mimxrt and stm32, or the
BTHCI interface which is is similar on supported ports. But sticking to
cases where the macros are the same across all ports.
This work was funded through GitHub Sponsors.
Signed-off-by: Angus Gratton <angus@redyak.com.au>
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.
