intel_th: pti: Use sysfs_match_string() helper

mainline inclusion
from mainline-v5.1-rc1
commit 1d2ef028
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I47H3V


CVE: NA

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Use sysfs_match_string() helper instead of open coded variant.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>