arm64: dts: renesas: r8a77970: add FCPVD support

Describe FCPVD0 in the R8A77970 device tree; it will be used by VSPD0 in
the next patch...

Based on the original (and large) patch by Daisuke Matsushita
<daisuke.matsushita.ns@hitachi.com>.
Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

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

@@ -617,6 +617,14 @@ avb: ethernet@e6800000 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 		};
+
+		fcpvd0: fcp@fea27000 {
+			compatible = "renesas,fcpv";
+			reg = <0 0xfea27000 0 0x200>;
+			clocks = <&cpg CPG_MOD 603>;
+			power-domains = <&sysc R8A77970_PD_ALWAYS_ON>;
+			resets = <&cpg 603>;
+		};
 	};
 
 	timer {