arm64: inline huge vmap supported functions

ascend inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4EUVI
CVE: NA

https://lwn.net/ml/linux-kernel/20200825145753.529284-8-npiggin@gmail.com/


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This allows unsupported levels to be constant folded away, and so
p4d_free_pud_page can be removed because it's no longer linked to.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Reviewed-by: Ding Tianhong <dingtianhong@huawei.com>
Reviewed-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>