ARM: bcm2835: add I2S driver to device tree

This adds the definitions for the BCM2835 I2S driver
to the device tree. Some GPIO settings are needed for
the correct pin functions.

Signed-off-by: Florian Meier <florian.meier@koalo.de>
[swarren: fixed DT node sort order, simplified DT label name, removed
RPI .dts file changs, since use of I2S is a user-added option.]
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>

arch/arm/boot/dts/bcm2835.dtsi

@@ -91,6 +91,16 @@
 			#interrupt-cells = <2>;
 		};
 
+		i2s: i2s@7e203000 {
+			compatible = "brcm,bcm2835-i2s";
+			reg = <0x7e203000 0x20>,
+			      <0x7e101098 0x02>;
+
+			dmas = <&dma 2>,
+			       <&dma 3>;
+			dma-names = "tx", "rx";
+		};
+
 		spi: spi@20204000 {
 			compatible = "brcm,bcm2835-spi";
 			reg = <0x7e204000 0x1000>;