mm/damon/core: pass per-region filter-passed bytes to damos_walk_control->walk_fn()

mm/damon/core: pass per-region filter-passed bytes to damos_walk_control->walk_fn()

Total size of memory that passed DAMON operations set layer-handled DAMOS
filters per scheme is provided to DAMON core API and ABI (sysfs interface)
users.  Having it per-region in non-accumulated way can provide it in
finer granularity.  Provide it to damos_walk() core API users, by passing
the data to damos_walk_control->walk_fn().

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: SeongJae Park <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>