Docs/ABI/damon: document 'schemes/<s>/tried_regions' sysfs directory

Update DAMON ABI document for the 'tried_regions' directory of DAMON
sysfs interface.

Link: https://lkml.kernel.org/r/20221101220328.95765-9-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>