Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Add information about the 845M card that I recently committed support
for.

Document Intel E7505 support.

Beautification.

First step in bringing this page up to speed:

Update list of supported bridges and controllers, use markup similar to
ata.4 to display them and replace an XFree86 xref with Xorg.

MFC after: 1 week

- Remove MLINKS to nonexistant manpages
- Change some section numbers to match reality
- For MLINKS to manpages from ports, mention which port installs them

MFC after: 3 days

mdoc(7): Use the new feature of the .In macro.

Use the -tag list to document agp(4) ioctls.

Document ioctl(2) operations of the agp(4) subsystem. The original patch
was obtained from [1], with heavy editing, and ammending text for some of
the ioctls.

All ioctls (in sys/agpio.h) are now documented.

PR: docs/50503
Original patch by: Alex Semenyaka <alexs@snark.ratmir.ru> [1]

Content approved by:

- Eric Anholt <anholt@FreeBSD.ORG>
- Matthew N. Dodd <mdodd@FreeBSD.ORG> (cursory review)

Approved and Reviewed by: des (mentor), re (scottl)

Add support for Intel's i820/i840/i845/i850/i860 chipset.

Submitted by: nork@cityfujisawa.ne.jp (Norikatsu Shigemura)

Fix a small style slip: Files in /dev are not
devices theirselves, but device nodes.

Move the agp(4) page from the i386 directory
to the machine-independent directory since
AGP is used on other architectures as well.