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

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

MFC: r234291, r234292

Add support for the Atmel SAM9XE family of microcontrollers, which
consist of a ARM926EJ-S processor core with up to 512 Kbytes of on-chip
flash. Tested with SAM9XE512.

MFC: r234281

- Try to bring these files closer to style(9).
- Use DEVMETHOD_END.
- Use NULL instead of 0 for pointers.

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

Approved by: re (implicit)

if_ate.c:

* Support for sam9 "EMAC" controller.
* Support for rmii interface to phy.

at91.c & at91sam9.c:

* Eliminate separate at91sam9.c file.
* Add new devices to at91sam9_devs table.

at91_machdep.c & at at91sam9_machdep.c:

* Automatic chip type determination.
* Remove compile time chip dependencies.
* Eliminate separate at91sam9_machdep.c file.

at91_pmc.c:

* Corrected support for all of the sam926? and sam9g20 chips.
* Remove compile time chip dependencies.

My apologies to Greg for taking so long to take care of it.

Store at91_master_clock in a global variable as opposed to a compile
time constant. This allows us to potentially change it at runtime or
autodetect it early in the boot (the latter being much more likely to
have a good outcome).

Start to make it easier to add AT91RM9200 based boards:
o Copy kb920x_machdep.c to at91_machdep.c
o Move board_init to new board_kb920x.c
o rename ramsize to at91_ramsize and make it accessible to board_* files.
o Delete files.kb920x. We can do this selection with the new boards.
o Add a stub for the tsc4370 board init, which will be added in
a future commit.
o Add new 'devices' at91_board_kb920x and at91_board_tsc4370. More are
needed and will be added in future commits.

Reviewed by: stass, cognet

Tweak the disclaimer section of the license to match COPYRIGHT, for
better or worse. Ok'd by folks that have additional copyrights to the
files in cases where there's joint authorship.

Import support for the Atmel AT91RM9200 CPU/Microcontroller. This SoC
is a ARM920T based CPU with a bunch of built-in peripherals. The
inital import supports the SPI bus, the TWI bus (although iicbus
integration is not complete), the uarts, the system timer and the
onboard ethernet. Support for the Kwikbyte KB9202
(http://www.kwikbyte.com) board is also included, although there's no
reason why the 9200 and the 9201 wouldn't also work. Primitive
support for running under the skyeye emulator is also provided
(although skyeye's support for the AT91RM9200 is a little weak).

The code has been structured so that other members of Atmel's arm family can
be supported in the future. The AT91SAM9260 is not presently supported
due to lack of hardware. The arm7tdmi families are also not supported
becasue they lack an MMU.

Many thanks to cognet@ for his help and assistance in bringing up this
board. He did much of the vm work and wrote parts of the uart and
system timer code as well as the bus space implementation.

The system boots to single user w/o problem, although the serial
console is a little slow and the ethernet driver is still in flux.

This work was sponsored by Timing Solutions, Corporation. I am
grateful to their support of the FreeBSD project in this manner.