[BUILD,FIX] small fix to create_class script

git-svn-id: https://open-ms.svn.sourceforge.net/svnroot/open-ms/OpenMS@10936 6adb6e08-d915-0410-941f-83917bcadc18
[FIX] another fix for the class generator; generated uncompilable code

git-svn-id: https://open-ms.svn.sourceforge.net/svnroot/open-ms/OpenMS@10937 6adb6e08-d915-0410-941f-83917bcadc18