perf arm-spe: Extract evsel setting up

perf arm-spe: Extract evsel setting up

The evsel for Arm SPE PMU needs to be set up. Extract the setting up
into a function arm_spe_setup_evsel().

Signed-off-by: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: James Clark <james.clark@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc:  <coresight@lists.linaro.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc:  <linux-perf-users@vger.kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>