Force TechRacer maps when image map is selected. Fixes Google Code issue #882 If you start a TechRacer map with an image map selected, the resulting map will likely to be completely unplayable. So this commit disables this.

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

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