D9334: Remove cmake 3.10+ warning for users of K_PLUGIN_FACTORY and K_PLUGIN_FACTORY_WITH_JSON

[David Faure]

dfaure accepted this revision.
This revision is now accepted and ready to land.

REPOSITORY
  R244 KCoreAddons

BRANCH
  remove_cmake_warning

REVISION DETAIL
  https://phabricator.kde.org/D9334

To: mlaurent, dfaure
Cc: #frameworks