Doc: link to QML module examples from qt_add_qml_module page

Users need code they can copy, and qt_add_qml_module lacks examples of
e.g. main.cpp and its position within the recommended directory
structure.

Pick-to: 6.2 6.3 6.4
Change-Id: I29212b603bfd9cf24ecb327317be8f1410b2cfda
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

src/qml/doc/src/cmake/qt_add_qml_module.qdoc

@@ -56,6 +56,9 @@ qt_add_qml_module(
 
 \versionlessCMakeCommandsNote qt6_add_qml_module()
 
+See \l {Building a QML application} and \l {Building a reusable QML module}
+for examples that define QML modules.
+
 \section1 Description
 
 This command defines a QML module that can consist of C++ sources, \c{.qml}