ramips: fix Sitecom WL-341v3 board and image names

The following patch changes:
 * board name from "wl341v3" to "wl-341v3"
 * dts filename
 * LED names in dts file

for Sitecom WL-341v3 device.

Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@46622 3c298f89-4303-0410-b956-a3cf2f4a3e73