staging: comedi: usbdux: remove unused define

This define is not used, and it's actually incorrect. The usbdux device
only has 4 analog output channels.

Remove it.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/usbdux.c

@@ -122,9 +122,6 @@ sampling rate. If you sample two channels you get 4kHz and so on.
 /* 16 bytes. */
 #define SIZEINSNBUF       16
 
-/* Number of DA channels */
-#define NUMOUTCHANNELS    8
-
 /* size of one value for the D/A converter: channel and value */
 #define SIZEDAOUT          ((sizeof(int8_t)+sizeof(int16_t)))