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/cpptools/baseeditordocumentparser.cpp

@@ -55,7 +55,7 @@ BaseEditorDocumentParser::BaseEditorDocumentParser(const QString &filePath)
     : m_filePath(filePath)
 {
     static int meta = qRegisterMetaType<ProjectPartInfo>("CppTools::ProjectPartInfo");
-    Q_UNUSED(meta);
+    Q_UNUSED(meta)
 }
 
 BaseEditorDocumentParser::~BaseEditorDocumentParser() = default;