The question is asked every time we enter a restaurant. And if you do smoke, do not smoke, even if your interviewer smokes.
Smoking is at an all-time low on the acceptance scale.
Even the smell of smoke on your clothes can count against you. If you smoke, do not smoke the day of the interview. In fact, do not smoke after your last shower prior to the interview. And wear fresh clothes which are free of the tobacco smell. But there are enough sensitive noses and prejudiced minds out there that you should do your very best to avoid any and all potential negatives.