mm/dynamic_pool: add tracepoints for dpool

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8S9BY


CVE: NA

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Add tracepoints for dynamic_hugetlb to track demotion, promotion, HugeTLB
reserved pages, HugeTLB page allocation and HugeTLB page free.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>