Optimise device unlink query

     OR steam_id IS NOT NULL

     OR email IS NOT NULL

     OR custom_id IS NOT NULL))

   OR EXISTS (SELECT id FROM user_device WHERE user_id = $1 AND id <> $2))`

   OR EXISTS (SELECT id FROM user_device WHERE user_id = $1 AND id <> $2 LIMIT 1))`

    res, err := tx.Exec(query, userID, in.Id)

		if err != nil {