It appears that in the 5 years since we deprecated this function, people
have not stopped using it. The removal of qt5_use_modules() caused lots of
troubles in packages still using it when they were compiled against Qt 5.11.0.
Instead, let's revive this function and keep it for the Qt5 life time.
See discussion on qt-development mailing list:
http://lists.qt-project.org/pipermail/development/2018-June/032837.html
Change-Id: Ic263e3bb6706268cb9ea38a0711665f166a3aa9e
Reviewed-by: David Faure <david.faure@kdab.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
a834b4d245