AFAICS /etc/sysconfig/kdump is generated with some fillup-template. In this case, obviously this does not work. So the first thing to do would be to ensure that there is ALWAYS an /etc/sysconfig/kdump if the kdump package needs it so desperately. I guess this whole thing is also supposed to work when installing an image without the help of YaST, so it should be self-contained with the kdump package always having reasonable defaults.