Stuttering easily falls under the definition of a disability and it would be illegal / immoral for a company to dock points for stuttering itself. Anyway, think of it as taking command of the situation. Best case, you tell them you're a person who stutters and proceed to have a normal interview. Worst case, the interview takes a bit longer because you stutter through some of your answers, but you've already made them aware that you're a person who stutters so they're not going to think you're nervous or unprepared. It's your dream company, so do everything you can to convey yourself honestly. Good luck and have fun!