kcrsid_setsid
kcr = kcrsid_setsid(kcr, &ksl->ksl_sids[0], KSID_GROUP);
cr->cr_ksid = kcrsid_setsid(cr->cr_ksid, ksp, index);
credsid_t *kcrsid_setsid(credsid_t *, ksid_t *, ksid_index_t);