instance per process. Virtual channels are placed in a queue, so there is
no longer a compile time limit of VAUDIOCHANS.
A new sysctl has been added to control multiple user access.
Mixer labels on virtual channels are now prefixed by vchan.
audiobell.c and audioctl have been updated to reflect these changes.
Use of fdclone was posted to tech-kern@ and improvements made.
Multiuser access control changes and the use of a queue were suggessted by
pgoyette@
f835d36292