ACPICA: Tables: Add full support for the DBG2 table.

Updates the DBG2 (Debug Port 2) table definition in the actbl2.h header.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

include/acpi/actbl2.h

@@ -327,6 +327,11 @@ struct acpi_table_dbg2 {
 	u32 info_count;
 };
 
+struct acpi_dbg2_header {
+	u32 info_offset;
+	u32 info_count;
+};
+
 /* Debug Device Information Subtable */
 
 struct acpi_dbg2_device {