Revert "mm/page_cache_limit: reconfiguration about page cache limit when memory plug/unplug"

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


CVE: NA

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

This reverts commit 955d63ae.
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>