Currently, ACRN only support shutdown when triple fault happens, because ACRN
doesn't present/emulate a virtual HW, i.e. port IO, to support shutdown. This
patch emulate a virtual shutdown component, and the vACPI method for guest OS
to use.
Pre-launched VM uses ACPI reduced HW mode, intercept the virtual sleep control/status
registers for pre-launched VMs shutdown
Tracked-On: #5411
Signed-off-by: dongshen <dongsheng.x.zhang@intel.com>