Revert "mm/page_cache_limit: add support for droping caches for target node"

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4HOXK


CVE: NA

--------------------------------

This reverts commit e56e8310.
This feature will be reimplement.

Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Reviewed-by: Tong Tiangen <tongtiangen@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>