Re: [PATCH v6 3/3] ls-files.c: add --deduplicate option

"ZheNing Hu via GitGitGadget" [off-list ref] writes:

Additional instructions:
In order to display entries information,`deduplicate` suppresses
the output of duplicate file names, not the output of duplicate
entries information, so under the option of `-t`, `--stage`, `--unmerge`,
`--deduplicate` will have no effect.

That information belongs to the end-user documentation.