Staging: at76_usb: update drivers/staging/at76_usb w/ mac80211 port

This updates drivers/staging/at76_usb to correspond with the latest
version previously available in wireless-testing.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/at76_usb/Kconfig

 config USB_ATMEL
 	tristate "Atmel at76c503/at76c505/at76c505a USB cards"
-	depends on WLAN_80211 && USB
+	depends on MAC80211 && WLAN_80211 && USB
 	default N
 	select FW_LOADER
 	---help---