When the IOMD isnt mapped and all is mapped 1:1 a read gives garbage and thus
the obscure feature that slows down printing (or halts it!) when the mouse
button is pressed during output to the vidcconsole gets allways activated.
Included a simple flag that signals if the IOMD is mapped; the delay routine
won't check the mouse if this flag is still clear.
- New versions of the drivers for the devices that really are IOMD
specific. The old arm32/mainbus drivers have either been rewritten
and are now child devices of the IOMD or they have been restructured
and split into generic drivers will IOMD specific attachments.