docs: trace: Add HiSilicon PTT device driver documentation

mainline inclusion
from mainline-remotes/origin/next
commit a7112b74
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5RP8T
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux.git/commit/?id=a7112b747c324dda8937d4f47b14dc0af0b465d1



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

Document the introduction and usage of HiSilicon PTT device driver as well
as the sysfs attributes description provided by the driver.

Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
[Fixed month and kernel version]
Link: https://lore.kernel.org/r/20220816114414.4092-5-yangyicong@huawei.com


Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Wangming Shao <shaowangming@h-partners.com>
Reviewed-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Jay Fang <f.fangjian@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>