It also fixes USB Power on MR3420v2.

Signed-off-by: Dmytro <dioptimizer@gmail.com>
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@37194 3c298f89-4303-0410-b956-a3cf2f4a3e73