diff: mark param1 and param2 as placeholders
Some l10n translators translated the parameters "files", "param1" and "param2" in the following message: "synonym for --dirstat=files,param1,param2..." Translating "param1" and "param2" is OK, but changing the parameter "files" is wrong. The parameters that are not meant to be used verbatim should be marked as placeholders, but the verbatim parameter not marked as a placeholder should be left as is. This change is a complement for commit 51e846e673 (doc: enforce placeholders in documentation, 2023-12-25). With the help of Jean-Noël,some parameter combinations in one placeholder (e.g. "<param1,param2>...") are splited into seperate placeholders. Helped-by: Jean-Noël Avila <jn.avila@free.fr> Signed-off-by: Jiang Xin <worldhello.net@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>