Update path of GPL includes (#690)

Author: christophfroehlich

example_12/controllers/include/passthrough_controller/passthrough_controller.hpp

@@ -25,7 +25,7 @@
 #include "realtime_tools/realtime_buffer.hpp"
 #include "std_msgs/msg/float64_multi_array.hpp"
 // auto-generated by generate_parameter_library
-#include "passthrough_controller_parameters.hpp"
+#include "ros2_control_demo_example_12/passthrough_controller_parameters.hpp"
 
 /**
  * PassthroughController is a simple chainable controller that exposes reference interfaces equal to