UPSTREAM: mm/damon/core: split out scheme stat update logic into a new function

The function for applying a given DAMON scheme action to a given DAMON
region, 'damos_apply_scheme()' is not quite short.  Make it better to read
by splitting out the stat update logic into a new function.

Link: https://lkml.kernel.org/r/20221026225943.100429-4-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

(cherry picked from commit d1cbbf62)

Bug: 300502883
Bug: 319753692
Change-Id: I1502a102cdd6959494c249b3633ff97af6ccb94c
Signed-off-by: cui yangpei <cuiyangpei@xiaomi.com>