sched: programmable: Add a tag for the task

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8OIT1



--------------------------------

Add a tag for the task, useful to identify the special task.
User can use the file system interface to mark different tags for
specific workloads.
The kernel subsystems can use the set_* helpers to mark it too.
The bpf prog obtains the tags to detect different workloads.

Signed-off-by: Chen Hui <judy.chenhui@huawei.com>
Signed-off-by: Ren Zhijie <renzhijie2@huawei.com>
Signed-off-by: Hui Tang <tanghui20@huawei.com>
Signed-off-by: Guan Jing <guanjing6@huawei.com>