ALSA: Fix uninintialized error return

Static analysis with cppcheck found the following error:
  [sound/core/init.c:118]: (error) Uninitialized variable: err

..this was introduced by commit 2471b6c8
("ALSA: info: Register proc entries recursively, too") where the call
to snd_info_card_register was removed and no longer setting the error
return in err.  When snd_info_create_card_entry fails to allocate a
an entry, the error path exits with garbage in err.  Fix is to return
-ENOMEM if entry fails to be allocated.

Fixes: 2471b6c8 ("ALSA: info: Register proc entries recursively, too")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/init.c

@@ -109,13 +109,12 @@ static void snd_card_id_read(struct snd_info_entry *entry,
 
 static int init_info_for_card(struct snd_card *card)
 {
-	int err;
 	struct snd_info_entry *entry;
 
 	entry = snd_info_create_card_entry(card, "id", card->proc_root);
 	if (!entry) {
 		dev_dbg(card->dev, "unable to create card entry\n");
-		return err;
+		return -ENOMEM;
 	}
 	entry->c.text.read = snd_card_id_read;
 	card->proc_id = entry;