f2fs-tools: fix endianness of on-disk check_sum in summary_footer
f2fs-tools: fix endianness of on-disk check_sum in summary_footer

Signed-off-by: Sheng Yong <ce77ec10379c6f281208b7b41f03fd701be51d81@huawei.com>
Signed-off-by: Jaegeuk Kim <71255387a32c360dfbe6dfb7aaeb123bf1dc8cb6@kernel.org>

TeamExodus/external_f2fs-tools,TeamExodus/external_f2fs-tools