mm/damon/core: commit damos->target_nid

mm/damon/core: commit damos->target_nid

When committing new scheme parameters from the sysfs, the target_nid field
of the damos struct would not be copied.  This would result in the
target_nid field to retain its original value, despite being updated in
the sysfs interface.

This patch fixes this issue by copying target_nid in damos_commit().

Link: https://lkml.kernel.org/r/20250709004729.17252-1-bijan311@gmail.com
Fixes: 83dc7bbaecae ("mm/damon/sysfs: use damon_commit_ctx()")
Signed-off-by: Bijan Tabatabai <bijantabatab@micron.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ravi Shankar Jonnalagadda <ravis.opensrc@micron.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>