ACPI: Make sysfs interface in ACPI power optional.

Reference: http://bugzilla.kernel.org/show_bug.cgi?id=9494

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --cc drivers/acpi/Kconfig
Simple merge

diff --cc drivers/acpi/ac.c
Simple merge

diff --cc drivers/acpi/battery.c
Simple merge

diff --cc drivers/acpi/sbs.c
Simple merge