staging: comedi: ni_labpc: fix labpc_calib_insn_read()

The comedi core expects the (*insn_read) operations to read insn->n
values and return the number of values actually read.

Make this function work like the core expects.
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/ni_labpc.c

@@ -1551,10 +1551,13 @@ static int labpc_calib_insn_read(struct comedi_device *dev,
 				 unsigned int *data)
 {
 	struct labpc_private *devpriv = dev->private;
+	unsigned int chan = CR_CHAN(insn->chanspec);
+	int i;
 
-	data[0] = devpriv->caldac[CR_CHAN(insn->chanspec)];
+	for (i = 0; i < insn->n; i++)
+		data[i] = devpriv->caldac[chan];
 
-	return 1;
+	return insn->n;
 }
 
 static int labpc_eeprom_insn_write(struct comedi_device *dev,