qcacld-3.0: Check tb[] pointer before access the content

In function wlan_hdd_check_is_acs_request_same(),
tb[QCA_WLAN_VENDOR_ATTR_ACS_LAST_SCAN_AGEOUT_TIME] is not checked
before dereference, it is optional if refer to this IE in function
__wlan_hdd_cfg80211_do_acs, correct this coding error.

Change-Id: I87262bd071d4dec9e6795bdf32ff7007cd2254d9
CRs-Fixed: 3585225

core/hdd/src/wlan_hdd_cfg80211.c

@@ -3574,7 +3574,7 @@ static bool wlan_hdd_check_is_acs_request_same(struct hdd_adapter *adapter,
 	if (sap_config->acs_cfg.master_acs_cfg.ch_width != ch_width)
 		return false;
 
-	if (nla_get_u32(tb[QCA_WLAN_VENDOR_ATTR_ACS_LAST_SCAN_AGEOUT_TIME])) {
+	if (tb[QCA_WLAN_VENDOR_ATTR_ACS_LAST_SCAN_AGEOUT_TIME]) {
 		last_scan_ageout_time =
 		nla_get_u32(tb[QCA_WLAN_VENDOR_ATTR_ACS_LAST_SCAN_AGEOUT_TIME]);
 	} else {