staging: comedi: rtd520: remove RtdAdcSampleCounter macro

This macro uses the 'devpriv' macro which relies on a local variable
having a specific name. It's also not used. Remove the macro.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/rtd520.c

@@ -406,10 +406,6 @@ struct rtdPrivate {
 
 /* Macros to access registers */
 
-/* ADC sample counter, 10bit */
-#define RtdAdcSampleCounter(dev, v) \
-	writel((v) & 0x3ff, devpriv->las0+LAS0_ADC_SCNT)
-
 /* User Timer/Counter (8254) */
 #define RtdUtcCounterGet(dev, n) \
 	readb(devpriv->las0 \