docs: process: fix broken link

http://linux.yyz.us/patch-format.html

 seems to be down since
approximately September 2018. There is a working archive copy on
arhive.org. Replaced the links in documenation + translations.

Signed-off-by: Jacob Huisman <jacobhuisman@kernelthusiast.com>
Reviewed-by: Federico Vaga <federico.vaga@vaga.pv.it>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>