ACPI: Record the Generic Error Status Block address

ACPI: Record the Generic Error Status Block address

Record the GHEB address via fw_cfg file, when recording
a error to CPER, it will use this address to find out
Generic Error Data Entries and write the error.

In order to avoid migration failure, make hardware
error table address to a part of GED device instead
of global variable, then this address will be migrated
to target QEMU.

Acked-by: Xiang Zheng <zhengxiang9@huawei.com>
Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20200512030609.19593-7-gengdongjiu@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>