D19965: kactivities: remove unused variable

[Gustavo Carneiro]

carneirogustavo added a reviewer: KActivities.

REPOSITORY
  R6 KActivities

REVISION DETAIL
  https://phabricator.kde.org/D19965

To: carneirogustavo, #kactivities
Cc: kde-frameworks-devel, michaelh, ngraham, bruns