Update these netgraph drivers in current so that these changes can be

Update these netgraph drivers in current so that these changes can be
MFC'ed i due time.  I can't test it under current right now because
netgraph seems to do unethical things with mutexes.

musycc:
	Add status per channel.
	Reduce printf chattyness
	Keep error counters line if_mn does.
	Increase descriptor count.

if_mn:
	Support experimental unframed E1 lines.

These two drivers should share more code relating to framed channelized
TDM media in general (T1/E1/E3/T3, Sonet).  Anyone interested email me.