kservice: don't resolve symlinks

KService has, since KDE 4, resolved the Nix store paths to the services
it detects when running kbuildsycoca. This patch uses QDir::cleanPath()
instead of QDir::canonicalPath(); the latter resolves symlinks while the
former does not. Both simplify the input (by removing ./, ../, etc.) so
this should be acceptable.
startkde: fix licence meta attribute
plasma5: fix typo in desktop-manager script
Revert "kservice: don't resolve symlinks"

This reverts commit 98b5377a86ed7acee4cc1488c352765e19a16cd2. The patch
was ineffective. Need to search the entire source tree for uses of
QDir::canonicalPath().