Despite SpatialAudio being a submodule of QtQuick3D, it is actually
implemented in qtmultimedia repository. The designer specifics for
QtMultimedia types are implemented in creator repository, so same was
done for SpatialAudio types.
Fixes: QDS-8530
Change-Id: I5a06125fa0b6910c17ca9838a35ff9c01a723056
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>