sw64: modify tc_sched_clock debugfs file

Sunway inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I56OLG



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Use debugfs_create_file() to create debugfs file for tc_sched_clock
so it is protected against file removals. Change its name to
"tc_sched_clock" to stay consistent with what we use in cmdline.

Signed-off-by: Mao Minkai <maominkai@wxiat.com>

Signed-off-by: Gu Zitao <guzitao@wxiat.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>