ACPI: IA64: fix allnoconfig build

The evils of Kconfig's select bite us once again...
ia64/Kconfig selects ACPI, which depends on PM.
But select ignores dependencies, allnoconfig
chooses CONFIG_PM=n, and thus the menu of sub-options
under ACPI vanish, which breaks the build.

Manually select PM along with ACPI for now.
Some day, we should delete them both, or fix select.

Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>