Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Import ACPICA 20090521.

Catch up with ACPI-CA 20070320 import.

Properly calculate the checksum of the APIC table.

Start each of the license/copyright comments with /*-

Replace misuse of NULL with 0UL.

Forced commit to note that this file was repocopied from ../libski.

Repocopy by: peter

Fix the build of libski now that we use the "official" MADT table
definitions. Those are slightly different than the ones we used
before ACPI-CA 20031203 got imported. No structural or functional
change.

Use __FBSDID().
Also some minor style cleanups.

Remove special casing for running in the simulator from the kernel
and instead add platform, firmware and EFI stubs to the loader.
The net effect of this change is that besides a special console and
disk driver, the kernel has no knowledge of the simulator. This has
the following advantages:
o Simulator support is much harder to break,
o It's easier to make use of more feature complete simulators.
This would only need a change in the simulator specific loader,
o Running SMP kernels within the simulator. Note that ski at this
time does not simulate IPIs, so there's no way to start APs.

The platform, firmware and EFI stubs describe the following hardware:
o 4 CPU Itanium,
o 128 MB RAM within the 4GB address space,
o 64 MB RAM above the 4GB address space.

NOTE: The stubs in the skiloader describe a machine that should in
parts be defined by the simulator. Things like processor interrupt
block and AP wakeup vector cannot be choosen at random because they
require interpretation by the simulator. Currently the simulator is
ignorant of this.

This change introduces an unofficial SSC call SSC_SAL_SET_VECTORS
which is ignored by the simulator.

Tested with: ski (version 0.943 for linux)