keep track of auxiliary definedness variable in mod and div
keep track of auxiliary definedness variable in mod and div

Previously:

   %?- X / Y #= Z #==> D, D = 1.
   %@ D = 1,
   %@ X in inf..sup,
   %@ _G3604 in inf..sup,
   %@ Y in inf..sup,
   %@ Z in inf..sup.

Now:

   %?- X / Y #= Z #==> D, D = 1.
   %@ D = 1,
   %@ X in inf..sup,
   %@ Y in inf..sup,
   %@ Z in inf..sup.

jn7163/swipl-devel,jn7163/swipl-devel,koryonik/swipl-devel,edechter/swipl-devel,edechter/swipl-devel,jn7163/swipl-devel,mndrix/swipl-devel,edechter/swipl-devel,mndrix/swipl-devel,mndrix/swipl-devel,koryonik/swipl-devel,jn7163/swipl-devel,edechter/swipl-devel,mndrix/swipl-devel,koryonik/swipl-devel,edechter/swipl-devel,jn7163/swipl-devel,mndrix/swipl-devel,koryonik/swipl-devel,koryonik/swipl-devel