dt/bindings: arm-boards: Remove skeleton.dtsi inclusion from example

As of commit 9c0da3cc ("ARM: dts: explicitly mark skeleton.dtsi
as deprecated"), including skeleton.dtsi is deprecated.
Hence remove it from the example.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/arm/arm-boards

@@ -148,11 +148,12 @@ Example:
 
 /dts-v1/;
 #include <dt-bindings/interrupt-controller/irq.h>
-#include "skeleton.dtsi"
 
 / {
 	model = "ARM RealView PB1176 with device tree";
 	compatible = "arm,realview-pb1176";
+	#address-cells = <1>;
+	#size-cells = <1>;
 
 	soc {
 		#address-cells = <1>;