dt-bindings: arm,gic: Fix binding example for a virt-capable GIC

The joys of copy/paste: the example of a virtualization capable GIC
in the DT binding was wrong, and propagated to dozens of platforms.
By having a GICC region that is only 4kB (instead of 8kB), we
end-up not being able to access the GICC_DIR register which is on
the second page.

Oh well. Let's fix the source of the crap before tackling individual
offenders.
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt

@@ -111,7 +111,7 @@ Example:
 		#interrupt-cells = <3>;
 		interrupt-controller;
 		reg = <0x2c001000 0x1000>,
-		      <0x2c002000 0x1000>,
+		      <0x2c002000 0x2000>,
 		      <0x2c004000 0x2000>,
 		      <0x2c006000 0x2000>;
 		interrupts = <1 9 0xf04>;