make sparc64 build ttyD{cfg,0,1,..,b}
move wscons) to 'target()' macros to make the above possible

millert@ ok

this feels alot like distrib/sets .. mi global and md for everybody that's
gotta be different ..

o properly generate scsi scanner devices
o shorten pty generation shell fragment
o many tweaks for vax (audio what? how did I ever think vax had audio?)