Documentation: Add missing event type for non-client mouse events

Documentation is missing the specialized event type names in the
non-client mouse event enum description.

Task-number: QTBUG-55018
Change-Id: Ica35994e13fc9a637a52eeca361898f8669fdbd1
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>

src/corelib/kernel/qcoreevent.cpp

@@ -170,10 +170,10 @@ QT_BEGIN_NAMESPACE
     \value LeaveEditFocus                   An editor widget loses focus for editing. QT_KEYPAD_NAVIGATION must be defined.
     \value LeaveWhatsThisMode               Send to toplevel widgets when the application leaves "What's This?" mode.
     \value LocaleChange                     The system locale has changed.
-    \value NonClientAreaMouseButtonDblClick A mouse double click occurred outside the client area.
-    \value NonClientAreaMouseButtonPress    A mouse button press occurred outside the client area.
-    \value NonClientAreaMouseButtonRelease  A mouse button release occurred outside the client area.
-    \value NonClientAreaMouseMove           A mouse move occurred outside the client area.
+    \value NonClientAreaMouseButtonDblClick A mouse double click occurred outside the client area (QMouseEvent).
+    \value NonClientAreaMouseButtonPress    A mouse button press occurred outside the client area (QMouseEvent).
+    \value NonClientAreaMouseButtonRelease  A mouse button release occurred outside the client area (QMouseEvent).
+    \value NonClientAreaMouseMove           A mouse move occurred outside the client area (QMouseEvent).
     \value MacSizeChange                    The user changed his widget sizes (\macos only).
     \value MetaCall                         An asynchronous method invocation via QMetaObject::invokeMethod().
     \value ModifiedChange                   Widgets modification state has been changed.