mac80211: ath9k: add GPIO support for AR9280 chip Enable access to GPIO on Atheros wireless chip AR9280. Support for 9280 is added to existing 9285/9287 subsystem because these 3 chips differ only in number of GPIO pins. Signed-off-by: Michal Cieslakiewicz <michal.cieslakiewicz@wp.pl> git-svn-id: svn://svn.openwrt.org/openwrt/trunk@49251 3c298f89-4303-0410-b956-a3cf2f4a3e73