selftests/damon/drgn_dump_damon_status: dump DAMOS filters

selftests/damon/drgn_dump_damon_status: dump DAMOS filters

drgn_dump_damon_status.py is a script for dumping DAMON internal status in
json format.  It is being used for seeing if DAMON parameters that are set
using _damon_sysfs.py are actually passed to DAMON in the kernel space.
It is, however, not dumping full DAMON internal status, and it makes
increasing test coverage difficult.  Add damos filters dumping for more
tests.

Link: https://lkml.kernel.org/r/20250720171652.92309-12-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>