arm64: dts: meson-gxm-nexbox-a1: Drop UART comment

Product pictures show no DB9 connector, so this seems copy&paste.
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>

arch/arm64/boot/dts/amlogic/meson-gxm-nexbox-a1.dts

@@ -113,7 +113,6 @@ hdmi_connector_in: endpoint {
 	};
 };
 
-/* This UART is brought out to the DB9 connector */
 &uart_AO {
 	status = "okay";
 	pinctrl-0 = <&uart_ao_a_pins>;