Add resources_lock_ lock_guards to avoid race condition when loading …

…robot_description through topic (ros-controls#1451)

hardware_interface/src/resource_manager.cpp

@@ -1012,6 +1012,7 @@ bool ResourceManager::load_and_initialize_components(
   const std::string sensor_type = "sensor";
   const std::string actuator_type = "actuator";
 
+  std::lock_guard<std::recursive_mutex> resource_guard(resources_lock_);
   for (const auto & individual_hardware_info : hardware_info)
   {
     // Check for identical names
@@ -1597,6 +1598,7 @@ return_type ResourceManager::set_component_state(
     return false;
   };
 
+  std::lock_guard<std::recursive_mutex> guard(resources_lock_);
   bool found = find_set_component_state(
     std::bind(&ResourceStorage::set_component_state<Actuator>, resource_storage_.get(), _1, _2),
     resource_storage_->actuators_);