make: fix if top_srcdir is global
make: fix if top_srcdir is global

MrTheodor/csg,MrTheodor/csg,votca/csg,votca/csg,junghans/csg,junghans/csg,junghans/csg,votca/csg,MrTheodor/csg,MrTheodor/csg,votca/csg,junghans/csg,junghans/csg,junghans/csg,MrTheodor/csg