Function safe_app::ffi::app_unregistered

#[no_mangle]
pub unsafe extern "C" fn app_unregistered(
    bootstrap_config: *const u8, 
    bootstrap_config_len: usize, 
    user_data: *mut c_void, 
    o_disconnect_notifier_cb: extern "C" fn(user_data: *mut c_void), 
    o_cb: extern "C" fn(user_data: *mut c_void, result: *const FfiResult, app: *mut App)
)

Create unregistered app. The user_data parameter corresponds to the first parameter of the o_cb and o_disconnect_notifier_cb callbacks.