[cmake] remove add_dune_alberta_flags from add_dumux_all_flags

The Alberta flags additionally need a space dimension and can only be
added for one such dimension. Thus, it is impossible to add all.

Reviewed by gruenich.



git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@13841 2fb0f335-1f38-0410-981e-8018bf24f1b0