Function bt_le_per_adv_sync_cb_unregister 

pub unsafe extern "C" fn bt_le_per_adv_sync_cb_unregister(
    cb: *mut bt_le_per_adv_sync_cb,
) -> c_int

@brief Unregister periodic advertising sync callbacks.

Removes the callback structure from the list of periodic advertising sync callbacks.

@param cb Callback struct.

@retval Zero on success or (negative) error code otherwise.