efi: Find mirrored memory ranges for arm64

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4PM01


CVE: NA

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Mirrored memory could be used on HiSilion's arm64 SoC. So efi_find_mirror()
is added in efi_init() so that systems can get memblock about any mirrored
ranges.

Co-developed-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>