ARM: dts: bcm2835-rpi: Drop unnecessary #address-cells/#size-cells

Compiling the bcm2835-rpi.dtsi with W=1 leads to the following warning:

Warning (avoid_unnecessary_addr_size): /soc/firmware: unnecessary
 #address-cells/#size-cells without "ranges" or child "reg" property

Fix this by removing these unnecessary properties.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Eric Anholt <eric@anholt.net>

arch/arm/boot/dts/bcm2835-rpi.dtsi

@@ -19,8 +19,6 @@ act {
 	soc {
 		firmware: firmware {
 			compatible = "raspberrypi,bcm2835-firmware", "simple-bus";
-			#address-cells = <0>;
-			#size-cells = <0>;
 			mboxes = <&mailbox>;
 		};