doors: Remove unnecessary nodebox and empty texture (#2662)

mods/doors/init.lua

@@ -78,9 +78,7 @@ end
 -- nodes from being placed in the top half of the door.
 minetest.register_node("doors:hidden", {
 	description = S("Hidden Door Segment"),
-	-- can't use airlike otherwise falling nodes will turn to entities
-	-- and will be forever stuck until door is removed.
-	drawtype = "nodebox",
+	drawtype = "airlike",
 	paramtype = "light",
 	paramtype2 = "facedir",
 	sunlight_propagates = true,
@@ -93,13 +91,7 @@ minetest.register_node("doors:hidden", {
 	drop = "",
 	groups = {not_in_creative_inventory = 1},
 	on_blast = function() end,
-	tiles = {"doors_blank.png"},
-	-- 1px transparent block inside door hinge near node top.
-	node_box = {
-		type = "fixed",
-		fixed = {-15/32, 13/32, -15/32, -13/32, 1/2, -13/32},
-	},
-	-- collision_box needed otherise selection box would be full node size
+	-- 1px block inside door hinge near node top
 	collision_box = {
 		type = "fixed",
 		fixed = {-15/32, 13/32, -15/32, -13/32, 1/2, -13/32},