arm64: dts: renesas: r8a77970: Add RWDT node

Add a device node for the Watchdog Timer (WDT) controller on the
Renesas R-Car V3M (r8a77970) SoC.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm64/boot/dts/renesas/r8a77970.dtsi

@@ -103,6 +103,16 @@ IRQ_TYPE_LEVEL_LOW)>,
 						  IRQ_TYPE_LEVEL_LOW)>;
 		};
 
+		rwdt: watchdog@e6020000 {
+			compatible = "renesas,r8a77970-wdt",
+				     "renesas,rcar-gen3-wdt";
+			reg = <0 0xe6020000 0 0x0c>;
+			clocks = <&cpg CPG_MOD 402>;
+			power-domains = <&sysc 32>;
+			resets = <&cpg 402>;
+			status = "disabled";
+		};
+
 		cpg: clock-controller@e6150000 {
 			compatible = "renesas,r8a77970-cpg-mssr";
 			reg = <0 0xe6150000 0 0x1000>;