drivers: iio: dac: ad5766: Fix dt property name

In the documentation the name for the property is
output-range-microvolts which is a standard name, therefore this name
must be used.

Fixes: fd9373e4 ("iio: dac: ad5766: add driver support for AD5766")
Signed-off-by: Mihail Chindris <mihail.chindris@analog.com>
Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Link: https://lore.kernel.org/r/20211007080035.2531-5-mihail.chindris@analog.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/dac/ad5766.c

@@ -503,13 +503,13 @@ static int ad5766_get_output_range(struct ad5766_state *st)
 	int i, ret, min, max, tmp[2];
 
 	ret = device_property_read_u32_array(&st->spi->dev,
-					     "output-range-voltage",
+					     "output-range-microvolts",
 					     tmp, 2);
 	if (ret)
 		return ret;
 
-	min = tmp[0] / 1000;
-	max = tmp[1] / 1000;
+	min = tmp[0] / 1000000;
+	max = tmp[1] / 1000000;
 	for (i = 0; i < ARRAY_SIZE(ad5766_span_tbl); i++) {
 		if (ad5766_span_tbl[i].min != min ||
 		    ad5766_span_tbl[i].max != max)