arm64: dts: imx8mq-pico-pi: Fix PMIC properties

Pass the required '#clock-cells' property and remove the invalid
'interrupt-names' property to fix the following schema warnings:

imx8mq-pico-pi.dtb: pmic@4b: '#clock-cells' is a required property
	from schema $id: http://devicetree.org/schemas/mfd/rohm,bd71837-pmic.yaml#
imx8mq-pico-pi.dtb: pmic@4b: 'interrupt-names' does not match any of the regexes: 'pinctrl-[0-9]+'
	from schema $id: http://devicetree.org/schemas/mfd/rohm,bd71837-pmic.yaml#Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq-pico-pi.dts

@@ -67,12 +67,12 @@ pmic: pmic@4b {
 		compatible = "rohm,bd71837";
 		pinctrl-names = "default";
 		pinctrl-0 = <&pinctrl_pmic>;
+		#clock-cells = <0>;
 		clocks = <&pmic_osc>;
 		clock-names = "osc";
 		clock-output-names = "pmic_clk";
 		interrupt-parent = <&gpio1>;
 		interrupts = <3 IRQ_TYPE_LEVEL_LOW>;
-		interrupt-names = "irq";
 
 		regulators {
 			buck1: BUCK1 {