message: Make Qt plugin targets optional
diff: @@ -30,6 +30,10 @@ else()
  endif()
  foreach(QT_PLUGIN ${QT_PLUGINS})
  + if(NOT TARGET Qt5::${QT_PLUGIN})
  + continue()
  + endif()
  +
  get_target_property(PLUGIN Qt5::${QT_PLUGIN} LOCATION_${CMAKE_BUILD_TYPE})
  get_filename_component(FILE_NAME ${PLUGIN} NAME)
  get_filename_component(DIR ${PLUGIN} DIRECTORY)
  