platform/chrome: pstore: Move to larger record size.

Accidentally specified a smaller record size, bring it back
to the same size as we had when we used the config file.

Signed-off-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Sameer Nanda <snanda@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>