make it possible to build xcfun without fortran interfaces
make it possible to build xcfun without fortran interfaces

we have some systems here without fortran support (yeah strange)
where it is difficult or expensive to install fortran
and xcint does not need fortran
by default fortran interfaces are there but it is now easy
to turn them off

dftlibs/xcfun,robertodr/xcfun,dftlibs/xcfun,robertodr/xcfun,bast/xcfun,dftlibs/xcfun,dftlibs/xcfun,robertodr/xcfun,robertodr/xcfun,bast/xcfun,bast/xcfun,bast/xcfun