staging: comedi: addi_apci_3120: use async->events to report hardware error

In apci3120_interrupt_dma(), use the async->events to report the hardware
error and allow the core to (*cancel) the command instead of calling the
(*cancel) function 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_apci3120.c

@@ -50,7 +50,7 @@ static void apci3120_interrupt_dma(int irq, void *d)
 		dev_err(dev->class_dev, "Interrupted DMA transfer!\n");
 	if (samplesinbuf & 1) {
 		dev_err(dev->class_dev, "Odd count of bytes in DMA ring!\n");
-		apci3120_cancel(dev, s);
+		async->events |= COMEDI_CB_ERROR;
 		return;
 	}
 	samplesinbuf = samplesinbuf >> 1;	/*  number of received samples */