MEDIUM: streams: Remove unnecessary call to srv_manage_queues()

MEDIUM: streams: Remove unnecessary call to srv_manage_queues()

Remove the call to srv_manage_queues() at the beginning of strem_free().
It is not needed. Before cur_sess was removed, it was bogusly using it
to check if the server was full, but process_srv_queue() was using
served anyway, so cur_sess was not reliable. At this point, served has
already be decremented, and process_srv_queue() was called, or it will
be later in stream_free(), but there is no point in doing that at the
beginning of steam_free().