riscv: dts: starfive: Enable axp15060 pmic for cpufreq

The VisionFive 2 board has an embedded pmic axp15060,
which supports the cpu DVFS through the dcdc2 regulator.
This patch enables axp15060 pmic and configs the dcdc2.

Signed-off-by: Mason Huo <mason.huo@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

arch/riscv/boot/dts/starfive/jh7110-starfive-visionfive-2.dtsi

@@ -114,6 +114,23 @@
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c5_pins>;
 	status = "okay";
+
+	axp15060: pmic@36 {
+		compatible = "x-powers,axp15060";
+		reg = <0x36>;
+		interrupts = <0>;
+		interrupt-controller;
+		#interrupt-cells = <1>;
+
+		regulators {
+			vdd_cpu: dcdc2 {
+				regulator-always-on;
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <1540000>;
+				regulator-name = "vdd-cpu";
+			};
+		};
+	};
 };
 
 &i2c6 {