QtScXML module does not export dependency on QML

libQtScXml links against libQtQml:

rw@rw-x220 lib$ ldd libQt5Scxml.so 
libQt5Qml.so.5 => /opt/Qt/5.12.3/gcc_64/lib/./libQt5Qml.so.5
libQt5Network.so.5 => /opt/Qt/5.12.3/gcc_64/lib/./libQt5Network.so.5
libQt5Core.so.5 => /opt/Qt/5.12.3/gcc_64/lib/./libQt5Core.so.5
...

 
But this dependency is not exported (from QTPATH/mkspecs/modules/qt_lib_scxml.pri):

QT.scxml.depends = core

qml is missing here. Thus, Qbs does not correctly set up the dependencies of the QtScXml module.

This bug is present at least since Qt 5.12, but it is hidden in projects having already a dependency on qml.