r92su: fixed wrong usb ids

{USB_DEVICE(0x0BDA, 0x8715)} should be
{USB_DEVICE(0x0BDA, 0x8175)}
                       ^^^

{USB_DEVICE(0x0009, 0x21E8)} should be
{USB_DEVICE(0x0009, 0x21E7)}
                         ^
Cc: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Xose Vazquez Perez <xose.vazquez@gmail.com>