Virt: ACPI: fix qemu assert due to re-assigned table data address

Virt: ACPI: fix qemu assert due to re-assigned table data address

acpi_data_push uses g_array_set_size to resize the memory size. If there
is no enough contiguous memory, the address will be changed. If we use
the old value, it will assert.
qemu-kvm: hw/acpi/bios-linker-loader.c:214: bios_linker_loader_add_checksum:
Assertion `start_offset < file->blob->len' failed.`

This issue only happens in building SRAT table now but here we unify the
pattern for other tables as well to avoid possible issues in the future.

Signed-off-by: Zhaoshenglong <zhaoshenglong@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>