panvk: expose EXT_display_control

We have a common implementation for this, let's just use that.

Similar to the previous commit, this is a bit silly. But if we ever get
in a situation where VK_EXT_display actually makes sense, this stuff
should "just work", so let's enable it for good measure.

Tested-by: Alexandre ARNOUD <aarnoud@me.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Part-of: <!33916>