This updates the Calxeda cpuidle driver to use PSCI calls to powergate
cores. This also enables cpuidle for the ECX-2000.
This could possibly become a generic PSCI driver, but there are no other
PSCI users in the kernel other than mach-virt.
Signed-off-by: Rob Herring <rob.herring@calxeda.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-pm@vger.kernel.org