Coach Fred Hoiberg doesn’t have to make a decision until Wednesday. And even then, he isn’t obligated to make any changes. By then, Hoiberg will have had two intense practices, film to study and some input from his staff and front office. Then maybe, just maybe, the “open competition’’ that Hoiberg called for at point guard after the embarrassing 101-69 loss Saturday to the Thunder will be a closed matter. According to one opposing basketball executive, however, it shouldn’t take that long. Jerian Grant won the starting job out of camp largely because Kris Dunn dislocated his left index finger midway through preseason play.