docs: clarify rules wrt tagging other people

docs: clarify rules wrt tagging other people

Point out that explicit permission is usually needed to tag other people
in changes, but mention that implicit permission can be sufficient in
certain cases. This fixes slight inconsistencies between Reported-by:
and Suggested-by: and makes the usage more intuitive.

While at it, explicitly mention the dangers of our bugzilla instance, as
it makes it easy to forget that email addresses visible there are only
shown to logged-in users.

The latter is not a theoretical issue, as one maintainer mentioned that
his employer received a EU GDPR (general data protection regulation)
complaint after exposing a email address used in bugzilla through a tag
in a patch description.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Simona Vetter <simona.vetter@ffwll.ch>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/588cf2763baa8fea1f4825f4eaa7023fe88bb6c1.1738852082.git.linux@leemhuis.info