staging: comedi: das08: rename DAS08_STATUS

The `DAS08_STATUS` macro contains the offset to the read-only status
register.  Rename it to `DAS08_STATUS_REG` and add a comment.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/das08.c

@@ -57,7 +57,7 @@
 #define DAS08_AI_LSB_REG	0x00	/* (R) AI least significant bits */
 #define DAS08_AI_MSB_REG	0x01	/* (R) AI most significant bits */
 #define DAS08_AI_TRIG_REG	0x01	/* (W) AI software trigger */
-#define DAS08_STATUS		2
+#define DAS08_STATUS_REG	0x02	/* (R) status */
 #define   DAS08_EOC			(1<<7)
 #define   DAS08_IRQ			(1<<3)
 #define   DAS08_IP(x)			(((x)>>4)&0x7)
@@ -205,7 +205,7 @@ static int das08_ai_eoc(struct comedi_device *dev,
 {
 	unsigned int status;
 
-	status = inb(dev->iobase + DAS08_STATUS);
+	status = inb(dev->iobase + DAS08_STATUS_REG);
 	if ((status & DAS08_EOC) == 0)
 		return 0;
 	return -EBUSY;
@@ -282,7 +282,7 @@ static int das08_di_rbits(struct comedi_device *dev, struct comedi_subdevice *s,
 			  struct comedi_insn *insn, unsigned int *data)
 {
 	data[0] = 0;
-	data[1] = DAS08_IP(inb(dev->iobase + DAS08_STATUS));
+	data[1] = DAS08_IP(inb(dev->iobase + DAS08_STATUS_REG));
 
 	return insn->n;
 }