ARM: u300: probe the U300 dummy-spichip from device tree

This probes the U300 dummy-spichip from the device tree
and adds the apropriate node to the tree.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/ste-u300.dts

@@ -233,6 +233,11 @@ spi: ssp@c0006000 {
 			num-cs = <3>;
 			#address-cells = <1>;
 			#size-cells = <0>;
+			spi-dummy@1 {
+				compatible = "arm,pl022-dummy";
+				reg = <1>;
+				spi-max-frequency = <20000000>;
+			};
 		};
 	};
 };

arch/arm/mach-u300/dummyspichip.c

@@ -263,10 +263,16 @@ static int pl022_dummy_remove(struct spi_device *spi)
 	return 0;
 }
 
+static const struct of_device_id pl022_dummy_dt_match[] = {
+	{ .compatible = "arm,pl022-dummy" },
+	{},
+};
+
 static struct spi_driver pl022_dummy_driver = {
 	.driver = {
 		.name	= "spi-dummy",
 		.owner	= THIS_MODULE,
+		.of_match_table = pl022_dummy_dt_match,
 	},
 	.probe	= pl022_dummy_probe,
 	.remove	= pl022_dummy_remove,