This patch adds the RFKill GPIO control switch and enables another GPIO to
control power supply to USB Ports by emulating an LED GPIO for WDR4900v1.

Signed-off-by: Guo Wei Lim <alphasparc@gmail.com>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@46279 3c298f89-4303-0410-b956-a3cf2f4a3e73