arm64: dts: meson-sm1-odroid-hc4: add regulators controlled by GPIOH_8

As described in the HC4 schematics, GPIOH_8 controls the USB 5V and 12V
regulators used to power the SATA drives.

And is set as Open Drain since this GPIO doesn't support Push-Pull.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20210607065435.577334-6-narmstrong@baylibre.com

arch/arm64/boot/dts/amlogic/meson-sm1-odroid-hc4.dts

@@ -44,6 +44,32 @@ led-red {
 		};
 	};
 
+	/* Powers the SATA Disk 0 regulator, which is enabled when a disk load is detected */
+	p12v_0: regulator-p12v_0 {
+		compatible = "regulator-fixed";
+		regulator-name = "P12V_0";
+		regulator-min-microvolt = <12000000>;
+		regulator-max-microvolt = <12000000>;
+		vin-supply = <&main_12v>;
+
+		gpio = <&gpio GPIOH_8 GPIO_OPEN_DRAIN>;
+		enable-active-high;
+		regulator-always-on;
+	};
+
+	/* Powers the SATA Disk 1 regulator, which is enabled when a disk load is detected */
+	p12v_1: regulator-p12v_1 {
+		compatible = "regulator-fixed";
+		regulator-name = "P12V_1";
+		regulator-min-microvolt = <12000000>;
+		regulator-max-microvolt = <12000000>;
+		vin-supply = <&main_12v>;
+
+		gpio = <&gpio GPIOH_8 GPIO_OPEN_DRAIN>;
+		enable-active-high;
+		regulator-always-on;
+	};
+
 	sound {
 		model = "ODROID-HC4";
 	};