perf cs-etm: Introducing function cs_etm__init_trace_params()

perf cs-etm: Introducing function cs_etm__init_trace_params()

The trace parameter initialisation code is repeated in two different
places, something that bloats the file and can lead to errors.  This
is fixed by introducing a helper function and calling the right
protocol initialisation code when required.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki K Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190212171618.25355-7-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>