osd_setup.cpp fix memleak

Origin commit data
------------------
Commit: 82a0cdeb68
Author: Jacek Jendrzej <overx300@gmail.com>
Date: 2017-09-18 (Mon, 18 Sep 2017)

src/gui/osd_setup.cpp

@@ -1516,6 +1516,7 @@ int COsdSetup::showContextChanlistMenu(CChannelList *parent_channellist)
 
 	int res = menu_chanlist->exec(NULL, "");
 	cselected = menu_chanlist->getSelected();
+	delete channellistNotifier;
 	delete menu_chanlist;
 	return res;
 }