[Bug-gnubg] Cosmetic bug in rollouts

[Philippe Michel]

On FreeBSD, compiled with USE_MULTITHREAD undefined.

When I start a rollout with the following stopping parameters :

- stop when JSD are small enough
- minimum 72 trials

and the decision is clear enough that the rollout is stopped by the 
second criteria, the GUI window shows "Finished (71 trials)", although an 
export of the position says that there were indeed 72 trials.

This appeared recently, probably with the multithreaded rollouts.