This is in line with e.g. qtbase. Also remove outdated/unreferenced
license files.
Change-Id: I5d3370ab453610f9c8165ff9e57db7ad4a785370
Reviewed-by: Jani Heikkinen <jani.heikkinen@qt.io>
(cherry picked from commit becb423e80)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>