Fix warning on undeclared global variable

shared_locked_xdoors2.lua

@@ -157,12 +157,11 @@ minetest.register_node("locks:door", {
             local fdir = 0
             local placer_pos = placer:get_pos()
             if placer_pos then
-                dir = {
+                fdir = minetest.dir_to_facedir({
                     x = above.x - placer_pos.x,
                     y = above.y - placer_pos.y,
                     z = above.z - placer_pos.z
-                }
+                })
-                fdir = minetest.dir_to_facedir(dir)
             end
 
             local t = 1