perf test: Add pmu-events test

perf test: Add pmu-events test

The initial test will verify that the test tables in generated pmu-events.c
match against known, expected values.

For known events added in pmu-events/arch/test, we need to add an entry
in test_cpu_aliases_events[] or test_uncore_events[].

A sample run is as follows for x86:

  john@linux-3c19:~/linux> tools/perf/perf test -vv 10
  10: PMU event aliases                                     :
  --- start ---
  test child forked, pid 5316
  testing event table bp_l1_btb_correct: pass
  testing event table bp_l2_btb_correct: pass
  testing event table segment_reg_loads.any: pass
  testing event table dispatch_blocked.any: pass
  testing event table eist_trans: pass
  testing event table uncore_hisi_ddrc.flux_wcmd: pass
  testing event table unc_cbo_xsnp_response.miss_eviction: pass
  test child finished with 0
  ---- end ----
  PMU event aliases: Ok

Signed-off-by: John Garry <john.garry@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: James Clark <james.clark@arm.com>
Cc: Joakim Zhang <qiangqing.zhang@nxp.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: linuxarm@huawei.com
[ Fixup test_cpu_events[] and test_uncore_events[] sentinels to initialize one of its members to NULL, fixing the build in older compilers ]
Link: http://lore.kernel.org/lkml/1584442939-8911-5-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>