arm64: zynqmp: Disable DP on kd240

When SOM dt is combined with kd240 overlay DPSUB is enabled but kd240 has
no DP wired that's why change disable it via status property.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/f6de217b3350c9d59032ef54800882e48f240398.1706791116.git.michal.simek@amd.com
diff --git a/arch/arm/dts/zynqmp-sck-kd-g-revA.dtso b/arch/arm/dts/zynqmp-sck-kd-g-revA.dtso
index b3fc17c..5202b7c 100644
--- a/arch/arm/dts/zynqmp-sck-kd-g-revA.dtso
+++ b/arch/arm/dts/zynqmp-sck-kd-g-revA.dtso
@@ -366,3 +366,7 @@
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_uart1_default>;
 };
+
+&zynqmp_dpsub {
+	status = "disabled";
+};