nubus: Remove slot zero probe

Some long forgotten changes from the linux-mac68k CVS:

Remove the slot 0 (ROM) probing.
Remove the pointless White Screen Of Death crap.

The original commit is here:

http://linux-mac68k.cvs.sourceforge.net/viewvc/linux-mac68k/linux-mac68k/drivers/nubus/nubus.c?r1=1.22.2.1&r2=1.22.2.2&pathrev=linux-2_2



This is mostly dead code removal. It is also a reversion to the
pre-v2.3.17 version. The old code was thoroughly tested in Debian Sarge.

The present code for probing fake slot resources in Apple's on-board
(slot zero) ROMs could be useful if replaced the macintosh_config struct.
But it can't do so and we don't want two mechanisms for identifying
on-board hardware.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>