Missing function declaration "diviu_rem" for older code

[Jens Schmidt <crashdump@meine-dateien.info>]

diviu_rem has been renamed to absdiviu_rem. Older Code will not compile
because there is no compatibility declaration to change calls from
diviu_rem to absdiviu_rem.

I thinks it's sufficient to add a declaration to pari/pariold.h. This
one liner would fix the problem:

  #define diviu_rem   absdiviu_rem


LG - Jens