uboot-kirkwood: update to 2012.04.01

iConnect board tested by:

Tim Fletcher <tim@night-shade.org.uk>
Wojciech Dubowik <wojciech.dubowik@neratec.com>

DockStar board tested by:

Martin Mueller <mm@sig21.net>

RaidSonic ICY BOX NAS6210 board tested by:

Luka Perkov <uboot@lukaperkov.net>

SheevaPlug was not tested but support for SheevaPlug is taken from upstream
uboot and it is not reported to be broken there.

SVN-Revision: 32717