iio: dac: ad7303: Add OF match table

The Documentation/devicetree/bindings/iio/dac/ad7303.txt DT binding doc
lists "adi,ad7303" as a compatible string but the corresponding driver
does not have an OF match table. Add the table to the driver so the SPI
core can do an OF style match.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/dac/ad7303.c b/drivers/iio/dac/ad7303.c
index fa28100..18a4ad5 100644
--- a/drivers/iio/dac/ad7303.c
+++ b/drivers/iio/dac/ad7303.c
@@ -281,6 +281,12 @@
 	return 0;
 }
 
+static const struct of_device_id ad7303_spi_of_match[] = {
+	{ .compatible = "adi,ad7303", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ad7303_spi_of_match);
+
 static const struct spi_device_id ad7303_spi_ids[] = {
 	{ "ad7303", 0 },
 	{}
@@ -290,6 +296,7 @@
 static struct spi_driver ad7303_driver = {
 	.driver = {
 		.name = "ad7303",
+		.of_match_table = of_match_ptr(ad7303_spi_of_match),
 		.owner = THIS_MODULE,
 	},
 	.probe = ad7303_probe,