ACPICA: acpidump: Convert the default behavior to dump from /sys/firmware/acpi/tables

ACPICA commit 04c3bd7e9d6aeb2b3edebe99c90dc271ae4e6353

In order to work without any additional option to dump tables when /dev/mem
doesn't exist, this patch switches the default behavior of acpidump to dump
from /sys/firmware/acpi/tables. Reported by Al Stone, Fixed by Lv Zheng.

Link: https://github.com/acpica/acpica/commit/04c3bd7e


Reported-by: Al Stone <ahs3@redhat.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>