iwl4965: fix rxon flags set to wrong value for A mode in .erp_ie_changed

The patch fixes a bug that enables RXON_FLG_TGG_PROTECT_MSK erroneously
for A mode in the erp_ie_changed mac80211 callback.
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl4965-base.c

@@ -7674,7 +7674,7 @@ static void iwl4965_mac_erp_ie_changed(struct ieee80211_hw *hw,
 	}
 
 	if (changes & IEEE80211_ERP_CHANGE_PROTECTION) {
-		if (cts_protection)
+		if (cts_protection && (priv->phymode != MODE_IEEE80211A))
 			priv->staging_rxon.flags |= RXON_FLG_TGG_PROTECT_MSK;
 		else
 			priv->staging_rxon.flags &= ~RXON_FLG_TGG_PROTECT_MSK;