How to make it so supports and other champs can have 6 items and still get a control ward.

Its simple, have an extra item slot just for a control ward. Simply put one of the major problems for control wards is they take up an inventory slot, which means come late game if you want a control ward you are sacrificing a 6th item. Now, since most of the time your ADC is not going to do that, or your top laner, or your jungler (unless it's Ivern but that's a different situation) or your mid laner, so the support is left only having 5 items and a control ward. My question is why is that even a thing? Just give us a trinket slot of a control ward, it'd make life a lot better for supports and would allow other players to contribute to using control wards. Since only one per person can be out at a time, it makes no sense to limit that even further by having it take up an item slot instead of having its own trinket slot.