AFAIK there's no obligation to provide one but if there's tv points in the house already you can reasonably assume they work since you can't exactly test these things before you move in. And of course if it used to work and it stops, there's an obligation to fix it.

With digital coming up soon it gets messy. A house might have a perfectly working analogue setup but won't work for digital. Going to cost a bit for landlords and make some business for TV installation folks.