ARM: dts: imx6qdl-apalis: mux HDMI CEC pin

Mux the HDMI CEC pin to make HDMI CEC working. With this change HDMI CEC
seems to work fine on a Apalis iMX6 on Ixora using cec-ctl.
Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-apalis.dtsi

@@ -200,7 +200,7 @@ ethphy: ethernet-phy@7 {
 
 &hdmi {
 	pinctrl-names = "default";
-	pinctrl-0 = <&pinctrl_hdmi_ddc>;
+	pinctrl-0 = <&pinctrl_hdmi_ddc &pinctrl_hdmi_cec>;
 	status = "disabled";
 };