message: examples: use vars to link, link to threads
diff: @@ -10,6 +10,7 @@ endif()
  find_package(MAVSDK REQUIRED)
  find_package(SDL2 REQUIRED)
  +find_package(Threads)
  add_executable(manual_control
  manual_control.cpp
  @@ -20,5 +21,6 @@ target_link_libraries(manual_control
  MAVSDK::mavsdk_action
  MAVSDK::mavsdk_telemetry
  MAVSDK::mavsdk
  - SDL2
  + ${SDL2_LIBRARIES}
  + ${CMAKE_THREAD_LIBS_INIT}
  )
  