fixed incompatibility in PRINTREC defined in sim.h and use in simi.c

The following bug has been fixed in mcsim/sim: sim.h defines
struct tagPRINTREC with member cTimes is an "int", while cTimes is
conditionally assigned "LONG_MAX" in GetPrintStep (in simi.c).

cTimes is now defined as a long.

The corrected sim.h file(in mcsim/sim) is available in the official 
CVS repository at http://savannah.gnu.org/projects/mcsim

Frederic