kernel/acpica: Add tunables for editing the _OSI string list.

ACPICA has a built-in list of supported _OSI strings. A query on any of
those strings returns TRUE. It is meant to help the ASL code determine
which OS it is dealing with. See AcpiDefaultSupportedInterfaces[] in
utosi.c for the full list.

This commit adds two tunables, hw.acpi.{install,remove}_interface,
for adding to and removing from that list. Their contents are comma
separated and leading white space is ignored.

Examples:

# Add "FreeBSD" to the list of supported _OSI strings,
# i.e. _OSI("FreeBSD") from ASL will return TRUE.
#
hw.acpi.install_interface="FreeBSD"

# Remove "Windows 2000" and "Windows 2001" from the list
# of supported _OSI strings, i.e. _OSI("Windows 2000") and
# _OSI("Windows 2001") from ASL will return FALSE.
#
hw.acpi.remove_interface="Windows 2000, Windows 2001"

Taken-from: FreeBSD
kernel/acpi: Stop installing default address space handlers explicitly.

Since ACPICA 20040427 this is no longer necessary since it is part of
AcpiEnableSubsystem(). It is not supported and has led to problems.

See http://svnweb.freebsd.org/base?view=revision&revision=212993
libc - change SEM_VALUE_MAX

sem_getvalue(3) requires a signed int count so change SEM_VALUE_MAX to INT_MAX.

Reviewed-by: joris@giovannangeli.fr
libc - bail out on invalid sem_open(3) flags

Preventing now callers from passing invalid flags prevents compatibility
issue should new flags be added to sem_open(3) in future standard
revisions.

Reviewed-by: joris@giovannangeli.fr
add posix semaphore test suite

Port FreeBSD test suite, remove tests specific to FreeBSD
implementation, and modify tests that do not comply with the standard.

A next step could be to integrate this test in dfregress(8).

Obtained-from:   FreeBSD
Reviewed-by: joris@giovannangeli.fr