ARM: EXYNOS: add secure firmware support to AFTR mode code
* Move cp15 registers saving to exynos_save_cp15() helper and add
additional helper usage to do_idle firmware method.
* Use resume firmware method instead of exynos_cpu_restore_register()
and skip exynos_cpu_save_register() on boards with secure firmware
enabled.
* Use sysram_ns_base_addr + 0x24/0x20 addresses instead of the default
ones used by exynos_cpu_set_boot_vector() on boards with secure
firmware enabled.
* Use do_idle firmware method instead of cpu_do_idle() on boards with
secure firmware enabled.
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>