please test pcm channel patch

[Sean Chittenden]

> > Hello All,
> > 	Please test this PCM patch.  It creates seperate locking
> > classes for PCM channels and should prevent the warning where
> > multiple mutexes from the same class are held (as reported
> > recently).  I believe this to be a good strategy as it masks fewer
> > errors.
> 
> I can confirm that this patch fixes my LOR for pcm(4).  -sc

Bah!  I got 30min into playing tunes and picked the same LOR up not
more than 5min after sending this. :(  Sorry for the false alarm.

acquiring duplicate lock of same type: "pcm record channel"
 1st pcm0:record:0 @ /usr/src/sys/dev/sound/pcm/dsp.c:144
 2nd pcm0:play:0 @ /usr/src/sys/dev/sound/pcm/dsp.c:146
Stack backtrace:

-sc

-- 
Sean Chittenden