qcacmn: Fix pmk_info null pointer dereference

In send_set_del_pmkid_cache_cmd_tlv(), pmk_info is
dereferenced to copy vdev_id, flush flag and other
parameters. Add null pointer validation for pmk_info before
dereferencing pmk_info.

Change-Id: If44acc76d7e0e5d4387f089f8ec5684fc4648665
CRs-Fixed: 2520041

wmi/src/wmi_unified_sta_tlv.c

@@ -1444,8 +1444,10 @@ static QDF_STATUS send_set_del_pmkid_cache_cmd_tlv(wmi_unified_t wmi_handle,
 	wmi_pmk_cache *pmksa;
 	uint32_t len = sizeof(*cmd);
 
-	if (pmk_info &&
-	    !pmk_info->is_flush_all)
+	if (!pmk_info)
+		return QDF_STATUS_E_INVAL;
+
+	if (!pmk_info->is_flush_all)
 		len += WMI_TLV_HDR_SIZE + sizeof(*pmksa);
 
 	buf = wmi_buf_alloc(wmi_handle, len);