when machdep.allowaperture sysctl is set to 3, allow concurrent access

Use .An in the AUTHORS section where appropriate;
from Kaspars at Bankovskis dot net

no such pages as XF86_Accel(1) or XF86_SVGA(1), so kill refs to them;

macpppc -> macppc

ok jmc

Retire OpenBSD/cats. Hardware is nice but prone to catch fire, and the firmware
is anything but useful. Nevertheless this was a very good platform to use as
an OpenBSD/*arm* starting point, but nowad

Retire OpenBSD/cats. Hardware is nice but prone to catch fire, and the firmware
is anything but useful. Nevertheless this was a very good platform to use as
an OpenBSD/*arm* starting point, but nowadays this platform is not necessary
anymore.

Somehow these CATS motherboard are just like AUI hubs, with the difference that,
when my AUI hub caught fire, 10base5 support was not removed from the networking
code.

show more ...

convert to new .Dd format;

"X Window System", in line with the rest of our docs;

deprive theo of his love for `Ns';

mention machdep.allowaperture can be lowered
(and remove mention of XFree86 snuck in here by someone who did NOT
understand how wrong that is)

update to reflect that this is also used for X.Org

and do some minor cleaning while here.

bits from matthieu, ok jmc

Remove OpenBSD/pegaos, this has been announced before but delayed until
the tree was stable. No point in code supporting a company which screws
its employees being in the OpenBSD tree.

A potpourri of Xr and layout fixes.

ok deraadt@

amd64/cats MI touches, as well as a few pegasos mentions forgotten.

- section reorder
- some macro fixes
- kill whitespace at EOL

typos;

wscons(4): ok miod@

aperture driver for alpha. It works here the same as on i386
to allow access to VGA card's memory by mmapping /dev/xf86.
The macdep.allowaperture does also control /dev/pci access.
Ok miod@, deraadt@

.Xr pci 4

sparc64 caveats

xf86 becomes a MI manpage