staging: vt6656: Fix oops on resume from suspend.

Remove usb_put_dev from vt6656_suspend and usb_get_dev
from vt6566_resume.

These are not normally in suspend/resume functions.

Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Cc: stable@vger.kernel.org # 3.0+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>