options USERCONFIG being present. Due to the lack of early boot hints
neither sio or sc would succeed the console probe. If USERCONFIG was
active, there was a second cninit() after userconfig had run and that
happened to make the console selection work. If you left out USERCONFIG,
you would end up with no console at all. :-(
This needs a proper fix, especially when sc looses the "at isa" hint.
But for now, this works.