intel_th: gth: Factor out trace start/stop

mainline inclusion
from mainline-v5.2-rc1
commit 9958e025
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I47H3V


CVE: NA

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The trace enable/disable functions of the GTH include the code that starts
and stops trace flom from the sources. This start/stop functionality will
also be used in the window switch trigger sequence.

Factor out start/stop code from the larger trace enable/disable code in
preparation for the window switch sequence.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>