ARM: dts: bcm281xx: change comment to C89 style

CodingStyle does not allow C99 style comments. Since the
dts files live in the kernel for now, make this compliant.
Signed-off-by: Matt Porter <matt.porter@linaro.org>
Acked-by: Christian Daudt <csd@broadcom.com>

arch/arm/boot/dts/bcm11351.dtsi

@@ -36,7 +36,7 @@ gic: interrupt-controller@3ff00100 {
 
 	smc@0x3404c000 {
 		compatible = "bcm,bcm11351-smc", "bcm,kona-smc";
-		reg = <0x3404c000 0x400>; //1 KiB in SRAM
+		reg = <0x3404c000 0x400>; /* 1 KiB in SRAM */
 	};
 
 	uart@3e000000 {