mm: sharepool: Charge Buddy hugepage to memcg

ascend inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6A3YT



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Charge buddy hugepage to memcg when kmemcg is disabled. If kmemcg
is enabled, we can also use kmemcg to charge buddy hugepages.

Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com>