ACPI: APEI: Fix BERT resources conflict with ACPI NVS area

It was reported that on some machines, there is overlap between ACPI
NVS area and BERT address range.  This appears reasonable because BERT
contents need to be non-volatile across reboot.  But this will cause
resources conflict in current Linux kernel implementation because the
ACPI NVS area is marked as busy.  The resource conflict is fixed via
excluding the ACPI NVS area when requesting IO resources for BERT.
When accessing the BERT contents, the whole BERT address range will be
ioremapped and accessed.

Reported-and-tested-by: Hans Kristian Rosbach <hansr@raskesider.no>
Signed-off-by: Ying Huang <ying.huang@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>