ARM: shmobile: lager: Enable DU device in DT

Specify the DU output topology, enable the DU device and configure the
related pins.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7790-lager.dts

@@ -144,16 +144,63 @@
 		states = <3300000 1
 			  1800000 0>;
 	};
+
+	vga-encoder {
+		compatible = "adi,adv7123";
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				adv7123_in: endpoint {
+					remote-endpoint = <&du_out_rgb>;
+				};
+			};
+			port@1 {
+				reg = <1>;
+				adv7123_out: endpoint {
+					remote-endpoint = <&vga_in>;
+				};
+			};
+		};
+	};
+
+	vga {
+		compatible = "vga-connector";
+
+		port {
+			vga_in: endpoint {
+				remote-endpoint = <&adv7123_out>;
+			};
+		};
+	};
+};
+
+&du {
+	pinctrl-0 = <&du_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	ports {
+		port@0 {
+			endpoint {
+				remote-endpoint = <&adv7123_in>;
+			};
+		};
+		port@2 {
+			lvds_connector: endpoint {
+			};
+		};
+	};
 };
 
 &extal_clk {
 	clock-frequency = <20000000>;
 };
 
 &pfc {
-	pinctrl-0 = <&du_pins>;
-	pinctrl-names = "default";
-
 	du_pins: du {
 		renesas,groups = "du_rgb666", "du_sync_1", "du_clk_out_0";
 		renesas,function = "du";