ARM: dts: imx: emcon-avari: Fix nxp,pca8574 #gpio-cells

According to the DT bindings, #gpio-cells must be two.

Fixes: 63e71fed ("ARM: dts: Add support for emtrion emCON-MX6 series")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-emcon-avari.dtsi

@@ -126,7 +126,7 @@ boardid: gpio@3a {
 		compatible = "nxp,pca8574";
 		reg = <0x3a>;
 		gpio-controller;
-		#gpio-cells = <1>;
+		#gpio-cells = <2>;
 	};
 };