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)

Use the preload_fetch_addr() and preload_fetch_size() convenience
functions to obtain the address and size of the overriding DSDT.

Sponsored by: Juniper Networks.

Import ACPICA 20090521.

Catch up with ACPI-CA 20070320 import.

Catch up with ACPI-CA 20051021 import

Canonize the include of acpi.h.

Standardize __FBSDID identifiers.

MFC after: 2 days

When the user overrides the DSDT, replace any SSDTs with a simple no-op
table. acpidump(8) concatenates the body of the DSDT and SSDTs so an
edited ASL will contain all the necessary information. We can't use a
completely empty table since ACPI-CA reports this as a problem.

MFC after: 3 days

Style fixes.

Fix hw.acpi.os_name by renaming it to hw.acpi.osname. The "_name" suffix
is reserved by the loader, and thus any tunable name with that suffix will
be silently discarded.

Document this in the header and man page so that other developers do not
develop so many bumps on the head after banging it against the wall.

Detective work by: Mark Santcroos, grehan

Add TUNABLE_STR to make "hw.acpi.os_name" more correct. However, the call
to getenv_string() still doesn't work.

Expand the check for overriding the OS name to override _OS* (including
_OS_, _OS, and _OSI). This should fix this option for people who reported
it not changing anything.

Support functions for the new ACPI import.
* AcpiOsDerivePciId(): finds a bus number, given the slot/func and the
acpi parse tree.
* AcpiOsPredefinedOverride(): use the sysctl hw.acpi.os_name to
override the value for _OS.

Ideas from: takawata, jhb
Reviewed by: takawata, marcel
Tested on: i386, ia64

Resolve conflicts arising from the ACPI CA 20020725 import.

Resolve conflicts arising from the ACPI CA 20020611 import.