6.0-BETA1/serial-console

this problem is not unique to 6.0, but since changes are happening with
tty/kb etc, i thougth it good idea to mention the problem:

if BIOS has serial port DISBABLED
and
/etc/ttys has ttyd0 on, this will HANG the system as soon as init
goes multiuser.

the hang is solid, so that BREAK/esc-to-debugger does not works.

danny