coresight: fix function etm_writel_cp14() parameter order

Function etm_writel_cp14() takes an offset and a value rather
than the other way around, something this patch is correcting.
The semantic remains the same since it is only a function stub.

Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>