coresight: etm4x: Modify core-commit to avoid HiSilicon ETM overflow

coresight: etm4x: Modify core-commit to avoid HiSilicon ETM overflow

The ETM device can't keep up with the core pipeline when cpu core
is at full speed. This may cause overflow within core and its ETM.
This is a common phenomenon on ETM devices.

On HiSilicon Hip08 platform, a specific feature is added to set
core pipeline. So commit rate can be reduced manually to avoid ETM
overflow.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
[Modified changelog title and Kconfig description]
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20201208182651.1597945-4-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>