ar71xx: mynet-n750: define LEDs connected to the AR8327 switch

Signed-off-by: Felix Kaechele <heffer@fedoraproject.org>
Patchwork: http://patchwork.openwrt.org/patch/4743/
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39361 3c298f89-4303-0410-b956-a3cf2f4a3e73