The idle control valve will get air from the throttle body regardless as to whether the coolant lines are connected or not, it's not affected by the position of the stat. The wax stat is naturally open allowing air to bypass the throttle plate and enter the inlet manifold. As the coolant temperature increases the heat expands the wax in the stat closing the valve and blocking off the air passage between the wax stat and inlet manifold side of the throttle plate.
If you were to remove the coolant feed to the throttle body the idle control valve would still do it's job, however the engine would also have a high idle due to the wax stat bleeding air past the throttle plate and into the inlet manifold. The idle control valve does not specifically need to take it's air feed from the throttle body, it just requires air that has passed through an air filter (as the air is going to enter the inlet manifold). You could simply remove that air hose from the throttle body and attach a small air filter to the end of it and the idle control valve will still function perfectly well.
If you want to remove the coolant feed to the throttle body and retain a normal idle control system, the obvious answer is to remove the throttle body from the inlet manifold, remove the wax stat from the throttle body, fill the area shaded in red (below photo) with some 2 part epoxy resin (Araldite, JB Weld, Super Steel etc...), apply a thin line of liquid gasket to where the blue line is (below photo), reinstall the wax stat to the throttle body, reinstall the throttle body to the inlet manifold (a new gasket would be a good idea) and reconnect the air feed to the idle control valve as normal.
The only problem I see with doing this is that the engine may suffer some idle/stalling issues during the first few minutes of a cold start(maybe 5°C and below). However this wouldn't be much of a problem if the car isn't a daily driver that's used most days of the year.