controllers/freeswitch: reorder the failure logic for no such user

controllers/freeswitch.moon

@@ -10,13 +10,14 @@ class Freeswitch extends lapis.Application
     POST: =>
       uid = @params["user"] or @params["sip_auth_username"]
       @user = Users\find extension: uid
+
+      if not @user
+        return status: 404, layout: false, "no such user " .. uid
+
       @tokens = Tokens\select "where user_id = ?", uid
 
       if #@tokens == 0
         return status: 404, layout: false, "no auth tokens for " .. uid
 
-      if not @user
-        return status: 404, layout: false, "no such user " .. uid
-
       render: true, layout: false
   }