Documentation: DT: Add documentation for ti,opa362 bindings

Signed-off-by: NMarek Belisko <marek@goldelico.com>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

Documentation/devicetree/bindings/video/ti,opa362.txt

+OPA362 analog video amplifier
+
+Required properties:
+- compatible: "ti,opa362"
+- enable-gpios: enable/disable output gpio
+
+Required node:
+- Video port 0 for opa362 input
+- Video port 1 for opa362 output
+
+Example:
+
+tv_amp: opa362 {
+	compatible = "ti,opa362";
+	enable-gpios = <&gpio1 23 0>;  /* GPIO to enable video out amplifier */
+
+	ports {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		port@0 {
+			reg = <0>;
+			opa_in: endpoint@0 {
+				remote-endpoint = <&venc_out>;
+			};
+		};
+
+		port@1 {
+			reg = <1>;
+			opa_out: endpoint@0 {
+				remote-endpoint = <&tv_connector_in>;
+			};
+		};
+	};
+};
+
+
+