Avoid warning on empty expressions

For some reason, Q_UNUSED includes already a semicolon, adding one
on the user side creates an additional empty statement.

Change-Id: I9c5e8fac381345a60792cb75e2938fd53958d3b0
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/fakevim/fakevimplugin.cpp

@@ -970,7 +970,7 @@ public:
 
     void setActive(const QString &needle, bool forward, FakeVimHandler *handler)
     {
-        Q_UNUSED(forward);
+        Q_UNUSED(forward)
         m_handler = handler;
         if (!m_handler)
             return;