proc: mem_reliable: Count reliable memory usage of reliable tasks

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8USBA


CVE: NA

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Counting reliable memory allocated by the reliable user tasks.

The policy of counting reliable memory usage is based on RSS statistics.
Anywhere with counter of mm need count reliable pages too. Reliable page
which is checked by page_reliable() need to update the reliable page
counter by calling reliable_page_counter().

Updating the reliable pages should be considered if the following logic is
added:
- add_mm_counter
- dec_mm_counter
- inc_mm_counter_fast
- dec_mm_counter_fast
- rss[mm_counter(page)]

Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>