Docs/mm/damon: fix spelling and grammar in monitoring_intervals_tuning_example.rst

Docs/mm/damon: fix spelling and grammar in monitoring_intervals_tuning_example.rst

This patch fixes some spelling and grammar mistakes in the documentation,
improving the readability.

- multipled  -> multiplied
- idential   -> identical
- minuts     -> minutes
- efficieny  -> efficiency

Link: https://lkml.kernel.org/r/20250217215512.12833-1-marcelomoreira1905@gmail.com
Signed-off-by: Marcelo Moreira <marcelomoreira1905@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Shuah khan <skhan@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>