Add an I/O port "device" to handle requests from the kernel to shutdown
or trigger a reboot, borrowing an I/O used for ACPI on the Q35 platform.
The details of this I/O port are included in the FADT
(SLEEP_STATUS_REG/SLEEP_CONTROL_REG/RESET_REG) with the details of the
value to write in the FADT for reset (RESET_VALUE) and in the DSDT for
shutdown (S5 -> 0x05)
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
