arm64: Do not try to bring up the cores disabled in DT node
arm64: Do not try to bring up the cores disabled in DT node

The macro DT_FOREACH_CHILD will iterates all child nodes ignoring the
status property, this patch changes to use DT_FOREACH_CHILD_STATUS_OKAY
to avoid trying to bring up disabled cores, which only iterates the
enabled child nodes.

Signed-off-by: Hou Zhiqiang <6c0c8902386def638715cb5c29c831cf16ec8aa4@nxp.com>

zephyrproject-rtos/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,galak/zephyr