staging: comedi: hwrdv_apci3200: use dev->read_subdev

Use the dev->read_subdev that was setup in the device attach instead
of accessing the dev->subdevices array directly.
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/addi-data/hwdrv_apci3200.c

@@ -2590,8 +2590,8 @@ static int i_APCI3200_CommandAnalogInput(struct comedi_device *dev,
 static int i_APCI3200_InterruptHandleEos(struct comedi_device *dev)
 {
 	struct addi_private *devpriv = dev->private;
+	struct comedi_subdevice *s = dev->read_subdev;
 	unsigned int ui_StatusRegister = 0;
-	struct comedi_subdevice *s = &dev->subdevices[0];
 
 	/* BEGIN JK 18.10.2004: APCI-3200 Driver update 0.7.57 -> 0.7.68 */
 	/* comedi_async *async = s->async; */