D26103: Put Q_REQUIRED_RESULT in front of the functions to fix builds with [[nodiscard]]

[Volker Krause]

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

REPOSITORY
  R241 KIO

BRANCH
  master

REVISION DETAIL
  https://phabricator.kde.org/D26103

To: vonreth, sitter, vkrause
Cc: kde-frameworks-devel, LeGast00n, GB_2, michaelh, ngraham, bruns