Docs/mm/damon/index: simplify the intro

Docs/mm/damon/index: simplify the intro

Patch series "Docs/mm/damon: update intro, modules, maintainer profile,
and misc".

Update DAMON documentations for wordsmithing, clarifications, and
miscellaneous outdated things with eight patches.  Patch 1 simplifies the
brief introduction of DAMON.  Patch 2 updates DAMON user-space tool
packaged distros information on design doc to include not only Fedora, but
refer to repology.  Three following patches update design and usage
documents for clarifying DAMON sample modules purposes (patch 3), and
outdated information about usages of DAMON modules (patches 4 and 5).
Final three patches update usage and maintainer-profile for sysfs
refresh_ms feature behavior (patch 6), synchronize DAMON MAINTAINERS
section name (patch 7), and broken damon-tests performance tests (patch
8).

This patch (of 8):

The intro is a bit verbose and redundant.  Simplify it by replacing
details with more links to the design docs, and refining the design points
list.

Link: https://lkml.kernel.org/r/20260118180305.70023-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20260118180305.70023-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>