KABI:reserve space for sched structures

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4KAP1?from=project-issue


CVE: NA

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We reserve some fields beforehand for sched structures prone to change,
therefore, we can hot add/change features of sched with this enhancement.
After reserving, normally cache does not matter as the reserved fields
are not accessed at all.

Signed-off-by: Guan Jing <guanjing6@huawei.com>
Reviewed-by: Chen Hui <judy.chenhui@huawei.com>
Reviewed-by: Cheng Jian <cj.chengjian@huawei.com>
Reviewed-by: Cheng Jian <cj.chengjian@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>