[media] media: rc: gpio-ir-recv: add support for device tree parsing

This patch adds device tree parsing for gpio_ir_recv platform_data and
the mandatory binding documentation. It basically follows what we already
have for e.g. gpio_keys. All required device tree properties are OS
independent but an optional property allows linux specific support for rc
maps.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

Documentation/devicetree/bindings/media/gpio-ir-receiver.txt

@@ -0,0 +1,16 @@
+Device-Tree bindings for GPIO IR receiver
+
+Required properties:
+	- compatible: should be "gpio-ir-receiver".
+	- gpios: specifies GPIO used for IR signal reception.
+
+Optional properties:
+	- linux,rc-map-name: Linux specific remote control map name.
+
+Example node:
+
+	ir: ir-receiver {
+		compatible = "gpio-ir-receiver";
+		gpios = <&gpio0 19 1>;
+		linux,rc-map-name = "rc-rc6-mce";
+	};