Update cmake for tutorial 712.

Former-commit-id: f18507914cb58708eeb9339e6a2367f8b9d5ffbb

tutorial/712_DataSmoothing/CMakeLists.txt

@@ -1,8 +1,5 @@
 cmake_minimum_required(VERSION 2.8.12)
 project(712_DataSmoothing)
 
-add_executable(${PROJECT_NAME}_bin
-  main.cpp)
-target_include_directories(${PROJECT_NAME}_bin PRIVATE ${LIBIGL_INCLUDE_DIRS})
-target_compile_definitions(${PROJECT_NAME}_bin PRIVATE ${LIBIGL_DEFINITIONS})
-target_link_libraries(${PROJECT_NAME}_bin ${LIBIGL_LIBRARIES} ${LIBIGL_VIEWER_EXTRA_LIBRARIES} ${LIBIGL_OPENGL_EXTRA_LIBRARIES} ${LIBIGL_OPENGL_GLFW_EXTRA_LIBRARIES})
+add_executable(${PROJECT_NAME}_bin main.cpp)
+target_link_libraries(${PROJECT_NAME}_bin igl::core igl::viewer tutorials)