Depends on:
- how much ironing you normally do / what sort of clothes you wear (do they really need to be ironed?)
- what sort of accommodation you're staying in
- what the rules are in your accommodation
Personally, I've always worn shirts that look terrible if they're not ironed, so I use an iron every day - whereas most people probably need an iron once a week or less at uni, in which case it's probably not worth the hassle or getting an ironing board in the car and the storage space in your (probably quite small) room.
If you're in traditional halls, there will probably be a laundry room with iron and ironing boards anyway. In some other types of accommodation (like groups of flats in different buildings), you might have to go outside to another building to ge to the laundry room. Halls' own irons and ironing boards can be quite dirty and have the remains of other people's burn clothes on them! Again, it depends how much ironing you're going to do whether these are problems for you or not.
Many halls will say you are not allowed to have your own iron. You might be able to hide an iron from room checks (although I wouldn't advocate this), but an ironing board is more difficult to hide - and the staff surely realise that where there's an ironing board, there's an iron not far away!