D5792: Fix installation folder for qm files in KDE Apps release settings

[Friedrich W. H. Kossebau]

kossebau created this revision.

REVISION SUMMARY
Old CMake code for estimating the installation dir of the qm files
was broken, did not match where the code is looking and thus the
traditional path as used before by the separate KDE Application
translation release tarballs as well code using libmarblewidget
and explicitely loading the translation with ecm_create_qm_loader,
as it is needed.

TEST PLAN
Works now for installation on Linux.
Android only theoretically tested ;)
Windows & macOS... no idea

REPOSITORY
R34 Marble

BRANCH
fixQMFilesInstallation

REVISION DETAIL
https://phabricator.kde.org/D5792

AFFECTED FILES
CMakeLists.txt
MarbleMacros.cmake

To: kossebau, rahn, nienhueser, ltoscano
Cc: marble-devel