staging: vt6656: [BUG] main_usb.c oops on device_close move flag earlier.
The vt6656 is prone to resetting on the usb bus.
It seems there is a race condition and wpa supplicant is
trying to open the device via iw_handlers before its actually
closed at a stage that the buffers are being removed.
The device is longer considered open when the
buffers are being removed. So move ~DEVICE_FLAGS_OPENED
flag to before freeing the device buffers.