dt-bindings: Add device tree binding for Goldfish RTC driver

Add documentation for DT binding of Goldfish RTC driver. The compatible
string used by OS for binding the driver is "google,goldfish-rtc".
Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Documentation/devicetree/bindings/rtc/google,goldfish-rtc.txt

+Android Goldfish RTC
+
+Android Goldfish RTC device used by Android emulator.
+
+Required properties:
+
+- compatible : should contain "google,goldfish-rtc"
+- reg        : <registers mapping>
+- interrupts : <interrupt mapping>
+
+Example:
+
+	goldfish_timer@9020000 {
+		compatible = "google,goldfish-rtc";
+		reg = <0x9020000 0x1000>;
+		interrupts = <0x3>;
+	};

MAINTAINERS

@@ -841,6 +841,11 @@ S:	Supported
 F:	drivers/android/
 F:	drivers/staging/android/
 
+ANDROID GOLDFISH RTC DRIVER
+M:	Miodrag Dinic <miodrag.dinic@imgtec.com>
+S:	Supported
+F:	Documentation/devicetree/bindings/rtc/google,goldfish-rtc.txt
+
 ANDROID ION DRIVER
 M:	Laura Abbott <labbott@redhat.com>
 M:	Sumit Semwal <sumit.semwal@linaro.org>