QmlDesigner: Add #include <QTextStream>

Amends d1b62588c5.

Change-Id: I10a6fe427087e60dd29b18488e15519a88fd77df
Reviewed-by: hjk <hjk@qt.io>

src/plugins/qmldesigner/generatecmakelists.cpp

@@ -39,6 +39,7 @@
 #include <QAction>
 #include <QRegularExpression>
 #include <QStringList>
+#include <QTextStream>
 
 using namespace Utils;