ALSA: seq: Degrade the error message for too many opens

ALSA OSS sequencer spews a kernel error message ("ALSA: seq_oss: too
many applications") when user-space tries to open more than the
limit.  This means that it can easily fill the log buffer.

Since it's merely a normal error, it's safe to suppress it via
pr_debug() instead.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/seq/oss/seq_oss_init.c

@@ -202,7 +202,7 @@ snd_seq_oss_open(struct file *file, int level)
 
 	dp->index = i;
 	if (i >= SNDRV_SEQ_OSS_MAX_CLIENTS) {
-		pr_err("ALSA: seq_oss: too many applications\n");
+		pr_debug("ALSA: seq_oss: too many applications\n");
 		rc = -ENOMEM;
 		goto _error;
 	}