Fix inconsistencies in guest nick name generation When the setting net/nick is empty, HW generates a guest name. But there were several problems: - Team name did not match guest name - Random guest number was re-rolled multiple times, causing inconsistencies - Guest number was often too large (now capped at 99999)

void fpcrtl_halt(int num) {
    __coverity_panic__();
}

int fpcrtl_abs(int num) {
    return num >= 0 ? num : -num;
}