thermal subsystem: iwyu

Tested: unit tests; just added a few used headers

Signed-off-by: Nan Zhou <nanzhoumails@gmail.com>
Change-Id: I3299f0445aedadd1411f4d3a407e9543197e22e1
diff --git a/redfish-core/lib/thermal_subsystem.hpp b/redfish-core/lib/thermal_subsystem.hpp
index 0d5b88b..390b294 100644
--- a/redfish-core/lib/thermal_subsystem.hpp
+++ b/redfish-core/lib/thermal_subsystem.hpp
@@ -1,11 +1,15 @@
 #pragma once
 
 #include "app.hpp"
+#include "logging.hpp"
 #include "query.hpp"
 #include "registries/privilege_registry.hpp"
 #include "utils/chassis_utils.hpp"
 #include "utils/json_utils.hpp"
 
+#include <optional>
+#include <string>
+
 namespace redfish
 {