No, not really. The browsers limit this in such a way that you have to capture something from a JavaScript event they fire when they want the install option to be exposed, so there isn't a link.
If it's applicable, it's shown on smaller devices on every page in the navigation menu. (If it's not shown, the browser hasn't triggered the event and thus the button wouldn't function anyway.)
They may always be able to add it manually via the browser menu, but you'd have to direct users to that.