arm64: dts: imx8mq: fix lcdif port node

The port node does not have a unit-address, remove it.
This fixes the warnings:
lcd-controller@30320000: 'port' is a required property
lcd-controller@30320000: 'port@0' does not match any of the regexes:
'pinctrl-[0-9]+'

Fixes: commit d0081bd0 ("arm64: dts: imx8mq: Add NWL MIPI DSI controller")
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq.dtsi

@@ -554,7 +554,7 @@ lcdif: lcd-controller@30320000 {
 				assigned-clock-rates = <0>, <0>, <0>, <594000000>;
 				status = "disabled";
 
-				port@0 {
+				port {
 					lcdif_mipi_dsi: endpoint {
 						remote-endpoint = <&mipi_dsi_lcdif_in>;
 					};