menue: add missing delete

Origin commit data
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Commit: 77643f3b3b
Author: vanhofen <vanhofen@gmx.de>
Date: 2017-09-25 (Mon, 25 Sep 2017)

Origin message was:
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- menue: add missing delete

src/gui/widget/menue.cpp

@@ -1208,6 +1208,7 @@ void CMenuWidget::calcSize()
 	*/
 	CMenuItem *separator = new CMenuSeparator();
 	height += separator->getHeight();
+	delete separator;
 	
 	//scrollbar width
 	scrollbar_width=0;