find qt5xml as dependency
Summary:
it's a public link target for the main library so we always need it found
seen used in
Analitza5Targets.cmake: INTERFACE_LINK_LIBRARIES "Qt5::Core;Qt5::Xml"
Test Plan:
- app using the target wants to link Qt5::Xml but doesn't know what that means
- apply patch
- app now actually knows what Qt5::Xml is and builds properly
Reviewers: apol
Reviewed By: apol
Subscribers: kde-edu
Tags: KDE Edu
Differential Revision: https://phabricator.kde.org/D22655