There are eight command inputs for 'state' DAMON sysfs file, and those are
verbosely explained in multiple paragraphs.  It is not easy to find
explanation of specific command, and getting whole picture of supported
commands.  Replace the paragraphs with a list.

Link: https://lkml.kernel.org/r/20231213190338.54146-7-sj@kernel.orgSigned-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>