config: add initial openeuler_defconfig for arm64

hulk inclusion
category: config
bugzilla: 45954
CVE: NA

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Based on openEuler 20.03, and enable more drivers and features.
Major config changes:

- use 52 BIT VA & PA.
- support more kunpeng drivers
Signed-off-by: NXie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>