carl9170: prevent speculative execution

CVE-2017-5753
CVE-2017-5715

Real commit text tbd
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
(cherry picked from commit 19299d3cee99e47bec3ace5d654eeb8fa6365bfd)
Signed-off-by: Andy Whitcroft <apw@canonical.com>

drivers/net/wireless/ath/carl9170/main.c

@@ -1388,6 +1388,7 @@ static int carl9170_op_conf_tx(struct ieee80211_hw *hw,
 
 	mutex_lock(&ar->mutex);
 	if (queue < ar->hw->queues) {
+		gmb();
 		memcpy(&ar->edcf[ar9170_qmap[queue]], param, sizeof(*param));
 		ret = carl9170_set_qos(ar);
 	} else {