[ALSA] Fix disconnection of proc interface

- Add the linked list to each proc entry to enable a single-shot
  disconnection (unregister)
- Deprecate snd_info_unregister(), use snd_info_free_entry()
- Removed NULL checks of snd_info_free_entry()

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/core/seq/seq_info.c b/sound/core/seq/seq_info.c
index 142e9e6..8a7fe5c 100644
--- a/sound/core/seq/seq_info.c
+++ b/sound/core/seq/seq_info.c
@@ -64,9 +64,9 @@
 
 int __exit snd_seq_info_done(void)
 {
-	snd_info_unregister(queues_entry);
-	snd_info_unregister(clients_entry);
-	snd_info_unregister(timer_entry);
+	snd_info_free_entry(queues_entry);
+	snd_info_free_entry(clients_entry);
+	snd_info_free_entry(timer_entry);
 	return 0;
 }
 #endif