Bluetooth Power Control API

src/btstack_control.h : The Bluetooth Hardware Control API allows HCI to manage Bluetooth chipsets via direct hardware controls.

typedef struct {
    void (*init) (const void *config);
    int  (*on)   (void);  // <-- turn BT module on and configure
    int  (*off)  (void);  // <-- turn BT module off
    int  (*sleep)(void);  // <-- put BT module to sleep    - only to be called after ON
    int  (*wake) (void);  // <-- wake BT module from sleep - only to be called after SLEEP
    void (*register_for_power_notifications)(void (*cb)(POWER_NOTIFICATION_t event));
} btstack_control_t;