atheros: add ieee80211_hw to ath_common

Make use of it on hw code in ath9k to avoid
using the ath9k ath_softc.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/main.c

@@ -1571,6 +1571,7 @@ static int ath_init_softc(u16 devid, struct ath_softc *sc, u16 subsysid)
 	common = ath9k_hw_common(ah);
 	common->ops = &ath9k_common_ops;
 	common->ah = ah;
+	common->hw = sc->hw;
 
 	/*
 	 * Cache line size is used to size and align various