ARM: dts: Blank D-Link DIR-685 console

Leaving this NAS with display and backlight on heats it up
and dissipates power. Turn off the screen after 4 minutes,
it comes back on when a user touches the keys.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/gemini-dlink-dir-685.dts

@@ -20,7 +20,7 @@ memory@0 {
 	};
 
 	chosen {
-		bootargs = "console=ttyS0,19200n8 root=/dev/sda1 rw rootwait";
+		bootargs = "console=ttyS0,19200n8 root=/dev/sda1 rw rootwait consoleblank=300";
 		stdout-path = "uart0:19200n8";
 	};