Function nm_client_activate_connection_async 

pub unsafe extern "C" fn nm_client_activate_connection_async(
    client: *mut NMClient,
    connection: *mut NMConnection,
    device: *mut NMDevice,
    specific_object: *const c_char,
    cancellable: *mut GCancellable,
    callback: GAsyncReadyCallback,
    user_data: gpointer,
)