Subqueue count displays incorrectly after adding a node on nodequeue tab

After adding a node to a subqqueue on the nodequeue tab at /node/[nid]/nodequeue , the subqueue count displays as being increased by 2 until the page is refreshed. This is because we're increasing the reported subqueue count before it's passed asynchronously by nodequeue_admin_add_node. This used to work until nodequeue_subqueue was made to increase the subqueue count in #446902: Same position in queue created when adding to nodequeue with VBO. Because the subqueue is now passed by reference to nodequeue_admin_add_node, increasing the subqueue count in calling functions is no longer necessary. Here's a patch.