Bugzilla: 3516 (https://bugzilla.tianocore.org/show_bug.cgi?id=3516) Make changes to ACPI 6.4 header according to the latest specification: - ACPI 6.4 January 2021, Section 5.2.25.2 System Physical Address (SPA) Range Structure, Table 5.109 - Mantis ID 1988 (https://mantis.uefi.org/mantis/view.php?id=1988) Also added a blank line between #defines and structure definitions to improve readability. Signed-off-by: Chris Jones <christopher.jones@arm.com> Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn> Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>