HMP: use per cpu cpuidle driver to fix deadlock in hmp_idle_pull

HMP: use per cpu cpuidle driver to fix deadlock in hmp_idle_pull

Using per cpu cpuidle driver to fix deadlock in hmp_idle_pull.
Otherwise a deadlock happened when do bl_idle_init.

[  113.878664] other info that might help us debug this:
[  113.878667]  Possible unsafe locking scenario:
[  113.878667]
[  113.878670]        CPU0
[  113.878673]        ----
[  113.878681]   lock(cpuidle_driver_lock);
[  113.878684]   <Interrupt>
[  113.878691]     lock(cpuidle_driver_lock);
[  113.878693]
[  113.878693]  *** DEADLOCK ***
[  113.878693]
[  113.878697] 1 lock held by ksoftirqd/4/28:
[  113.878719]  #0:  (hmp_force_migration){+.....}, at: [<c0054da5>]
hmp_idle_pull+0x49/0x508

This patch is just a quick/cheap workaround for cpuidle_driver_lock
deadlock. It works for TC2 and any other platform where the idle
driver cannot be changed at runtime.

Signed-off-by: Alex Shi <alex.shi@linaro.org>
Signed-off-by: Jon Medhurst <tixy@linaro.org>