Where we mean the Qt Qml module, the "Qml" is to be written in regular
upper case, not all caps. Also, the Qt Qml XmlListModel has a "Qml" in
its name. This makes it easier to understand the documentation tree.

Fixes: QTBUG-35866
Change-Id: I148727d7abb12077bc25d992853727bbc165b27d
Reviewed-by: Alexei Cazacov <alexei.cazacov@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>