The DSL-2740B/DSL-2741B rev C2 support was missing the board definition,
resulting in a kernel panic on boot.
This patch adds it, and also renames the generated image name to properly
reflect that it is for the revision C2, and for both the DSL-2740B and
DSL-2741B.
Signed-off-by: Jonas Gorski <jonas.gorski+openwrt@gmail.com>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@24188 3c298f89-4303-0410-b956-a3cf2f4a3e73
