ath9k: Fix a smatch warnings

Smatch shows the following warnings:

  CHECK   drivers/net/wireless/ath/ath9k/htc_drv_main.c
drivers/net/wireless/ath/ath9k/htc_drv_main.c +1315 ath9k_htc_configure_filter(27) warn: inconsistent returns mutex:&priv->mutex: locked (1303) unlocked (1315)

  CHECK   drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
drivers/net/wireless/ath/ath9k/ar9003_eeprom.c +3321 ar9300_eeprom_restore_internal(20) warn: returning -1 instead of -ENOMEM is sloppy
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/ar9003_eeprom.c

@@ -3318,7 +3318,7 @@ static int ar9300_eeprom_restore_internal(struct ath_hw *ah,
 
 	word = kzalloc(2048, GFP_KERNEL);
 	if (!word)
-		return -1;
+		return -ENOMEM;
 
 	memcpy(mptr, &ar9300_default, mdata_size);
 

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

@@ -1300,6 +1300,7 @@ static void ath9k_htc_configure_filter(struct ieee80211_hw *hw,
 	if (priv->op_flags & OP_INVALID) {
 		ath_dbg(ath9k_hw_common(priv->ah), ATH_DBG_ANY,
 			"Unable to configure filter on invalid state\n");
+		mutex_unlock(&priv->mutex);
 		return;
 	}
 	ath9k_htc_ps_wakeup(priv);