It used to be that hitting the refresh arrow/loop button in preferences -> account would pull down a new provisioning profile with all ur new devices.
Now it just downloads the ones you already have. But if the one you need updated is managed by Xcode, theres's no way I can find to add a device to it!
See Question&Answers more detail:
os 与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…