qdoc: Auto-linking to functions are sometimes resolved incorrectly

Auto-linking to functions (strings that end with '()') sometimes can also be resolved to QML types. The correct action would be to not create a link at all if the autolinking doesn't resolve to a function.

http://doc-snapshot.qt-project.org/qt5-stable/qtwidgets-widgets-mousebuttons-example.html

• search for 'wheelEvent()' -> links to WheelEvent QML type

http://doc-snapshot.qt-project.org/qt5-stable/qfilesystemmodel.html#details

• search for 'path()' -> links to Path QML type

Note: Both of these examples are errors in the documentation and will be fixed, but they demonstrate the invalid linking issue. These are hard to spot as they don't generate any warnings.