ARM: dts: imx6qdl-phytec-pfla02: add missing interrupt-controller property

The DA9063 device need the required "interrupt-controller" property as
documented by the bindings [1].

[1] Documentation/devicetree/bindings/mfd/da9063.txt
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-phytec-pfla02.dtsi

@@ -117,6 +117,7 @@ pmic@58 {
 		reg = <0x58>;
 		interrupt-parent = <&gpio2>;
 		interrupts = <9 IRQ_TYPE_LEVEL_LOW>; /* active-low GPIO2_9 */
+		interrupt-controller;
 
 		regulators {
 			vddcore_reg: bcore1 {