This ensures that we only find Qt5 modules from the same directory
as modules we have already found, not from multiple different
directories which may be incompatible.
Change-Id: I7ad1d81ec41bba2e543130740041338ba44a6c3b
Reviewed-by: Alexander Neundorf <neundorf@kde.org>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>