ath9k_htc: avoid kernel panic in ath9k_hw_reset

hw pointer of ath_hw is not assigned to proper value
in function ath9k_hw_reset what finally causes kernel panic.
This can be solved by proper initialization of ath_hw in
ath9k_init_priv.

Signed-off-by: Marek Puzyniak <marek.puzyniak@tieto.com>
Acked-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -464,6 +464,7 @@ static int ath9k_init_priv(struct ath9k_htc_priv *priv,
 		return -ENOMEM;
 
 	ah->dev = priv->dev;
+	ah->hw = priv->hw;
 	ah->hw_version.devid = devid;
 	ah->hw_version.usbdev = drv_info;
 	ah->ah_flags |= AH_USE_EEPROM;