ARM: mvebu: use stdout-path in all armada-*.dts

This commit adds the stdout-path property in /chosen for all Armada
boards that were not yet carrying this property, and gets rid of
/chosen/bootargs which becomes unneeded: earlyprintk should not be
used by default, and the console= parameter is replaced by the
/chosen/stdout-path property.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

arch/arm/boot/dts/armada-xp-openblocks-ax3-4.dts

@@ -54,7 +54,7 @@
 	compatible = "plathome,openblocks-ax3-4", "marvell,armadaxp-mv78260", "marvell,armadaxp", "marvell,armada-370-xp";
 
 	chosen {
-		bootargs = "console=ttyS0,115200 earlyprintk";
+		stdout-path = "serial0:115200n8";
 	};
 
 	memory {