Pull ACPI fixes from Rafael Wysocki:
"Two fixes here, one revert of a recent ACPICA commit that broke audio
support on one Dell machine and a fix for a long-standing issue that
may cause systems to break randomly during boot.
Specifics:
- The recent ACPICA commit that set the ACPI _REV return value to 2
(which is the value always used by Windows and now mandated by the
spec too) in order to prevent the firmware people from using it to
play tricks with us caused a serious audio regression to happen on
Dell XPS 13 (the AML on that machine uses the _REV return value to
decide how to expose audio to the OS and does that to hide the lack
of proper support for its I2S audio in Linux), so revert that
commit for now and we'll revisit the issue in the next cycle.
- Ensure that the ordering of acpi_reserve_resources() with respect
to the rest of the ACPI initialization sequence will always be the
same, or the IO or memory region occupied by the ACPI fixed
registers may be assigned to a PCI host bridge as a result of a
race and random breakage ensues going forward"
* tag 'pm+acpi-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Revert "ACPICA: Permanently set _REV to the value '2'."
ACPI / init: Fix the ordering of acpi_reserve_resources()