ARM: at91/dt: at91-kizbox: update chosen node

Simplify the bootargs since the platform is booting from an initramfs and
set the kernel stdout path to DBGU.

Signed-off-by: Gaël PORTAY <g.portay@overkiz.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/boot/dts/at91-kizbox.dts

@@ -15,7 +15,8 @@
 	compatible = "overkiz,kizbox", "atmel,at91sam9g20", "atmel,at91sam9";
 
 	chosen {
-		bootargs = "panic=5 ubi.mtd=1 rootfstype=ubifs root=ubi0:root";
+		bootargs = "ubi.mtd=ubi";
+		linux,stdout-path = &dbgu;
 	};
 
 	memory {