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

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

commit da10816e3d923565b470fec78a674baba794ed33 upstream.

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.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.2: this was still using snd_printk()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>