PM / Runtime: Kconfig: move ia64 dependency to arch/ia64/Kconfig

The IA64_HP_SIM dependency on PM_RUNTIME should be done in the arch
Kconfig instead of in the PM core.  Move it accordingly.

NOTE: arch/ia64/Kconfig currently does a 'select PM', which since
commit 1eb208aea317 (PM: Make CONFIG_PM depend on (CONFIG_PM_SLEEP ||
CONFIG_PM_RUNTIME)) is effectively a noop unless PM_SLEEP or
PM_RUNTIME are set elsewhere.

Signed-off-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>