D5865: Add missing KDE_ENABLE_NAMED_OPERATORS function

[René J . V . Bertin]

rjvbb set the repository for this revision to R240 Extra CMake Modules.

REPOSITORY
  R240 Extra CMake Modules

REVISION DETAIL
  https://phabricator.kde.org/D5865

To: rjvbb, #frameworks, #build_system, cgilles
Cc: kfunk