Docs/admin-guide/mm/damon/start: update DAMOS example command

DAMON user-space tool, damo, has deprecated[1] its old DAMOS schemes
specification format.  However, an example of DAMON documentation is still
using it.  Update the example to use one of the alternative options.

[1] https://github.com/awslabs/damo/commit/e9950ae68f6c

Link: https://lkml.kernel.org/r/20230616191742.87531-3-sj@kernel.org


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