When working with USB devices we need to use DMA-safe buffers,
and iforce->edata is not one. Let's rework the code to allocate
temporary buffer (iforce_get_id() is called only during initialization
so there is no reason to have permanent buffer) and use it. While at it,
let's utilize usb_control_msg() API which simplifies code.
Tested-by: Tim Schumacher <timschumi@gmx.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>