It should be implemmented in a cleaner way.
This reverts the following commits:
[ar71xx] dir-825-b1: Fix wholeflash images
[ar71xx] dir825b1: Add image for DIR-825-B1 that uses the whole flash"
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@33459 3c298f89-4303-0410-b956-a3cf2f4a3e73