Pull ACPI and power management fixes from Rafael Wysocki:
"These fix one recent cpufreq regression, a few older bugs that may
harm users and a kerneldoc typo.
Specifics:
1) After the recent locking changes in the cpufreq core it is
possible to trigger BUG_ON(!policy) in lock_policy_rwsem_read() if
cpufreq_get() is called before registering a cpufreq driver. Fix
from Viresh Kumar.
2) If intel_pstate has been loaded already, it doesn't make sense to
do anything in acpi_cpufreq_init() and moreover doing something in
there in that case may be harmful, so make that function return
immediately if another cpufreq driver is already present. From
Yinghai Lu.
3) The ACPI IPMI driver sometimes attempts to acquire a mutex from
interrupt context, which can be avoided by replacing that mutex
with a spinlock. From Lv Zheng.
4) A NULL pointer may be dereferenced by the exynos5440 cpufreq
driver if a memory allocation made by it fails. Fix from Sachin
Kamat.
5) Hanjun Guo's commit fixes a typo in the kerneldoc comment
documenting acpi_bus_unregister_driver()"
* tag 'pm+acpi-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / scan: fix typo in comments of acpi_bus_unregister_driver()
cpufreq: exynos5440: Fix potential NULL pointer dereference
cpufreq: check cpufreq driver is valid and cpufreq isn't disabled in cpufreq_get()
acpi-cpufreq: skip loading acpi_cpufreq after intel_pstate
ACPI / IPMI: Fix atomic context requirement of ipmi_msg_handler()