FROMLIST: tools: sg_write_buffer: add sg_write_buffer for FFU

(am from https://sourceforge.net/p/linux-f2fs/mailman/message/36260998/)

sg_write_buffer sources are added for FFU.

Bug: 74000758
Change-Id: Ibbe959b58df5b1baa54d1542660c598876ac67b7
Merged-In: Ibbe959b58df5b1baa54d1542660c598876ac67b7
Signed-off-by: Hyojun Kim <hyojun@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
30 files changed