ACPI: convert to sysfs framework

Setup new sysfs framework

1.	Remove /sys/firmware/acpi
2.	Add ACPI device in device tree.

File "eject" for every device that has _EJ0 method is moved from
/sys/firmware to /sys/devices.
Operation on this file is exactly the same as before.
i.e. echo 1 to "eject" will cause hot removal of this device.
Corresponding changes should be made in userspace for hot removal.

Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Zhang Rui<rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>