perf test: Make matching_pmu effective

The perf_pmu_test_event.matching_pmu didn't work. No matter what its
value is, it does not affect the test results. So let matching_pmu be
used for matching perf_pmu_test_pmu.pmu.name.

Signed-off-by: Jing Zhang <renyu.zj@linux.alibaba.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Tested-by: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Shuai Xue <xueshuai@linux.alibaba.com>
Cc: Zhuo Song <zhuo.song@linux.alibaba.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/1695794391-34817-5-git-send-email-renyu.zj@linux.alibaba.com


Signed-off-by: Namhyung Kim <namhyung@kernel.org>