ARM: dts: axp22x.dtsi: Add reg_drivebus node

Add a node describing the drivebus regulator which is an (optional)
part of the axp221/axp223 pmic. Since this regulator may not be
available at all depending on the board, mark it as disabled by
default.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/axp22x.dtsi

@@ -141,6 +141,11 @@
 			regulator-max-microvolt = <3000000>;
 			regulator-name = "rtc_ldo";
 		};
+
+		reg_drivevbus: drivevbus {
+			regulator-name = "drivevbus";
+			status = "disabled";
+		};
 	};
 
 	usb_power_supply: usb_power_supply {