perf tests: Add test for PMU aliases

A perf uncore PMU may have two PMU names, a real name and an alias.

Add one test case to verify that the real and alias names have the same
effect.

Iterate sysfs to get one event which has an alias and create an evlist
by adding two evsels. Evsel1 is created by event and evsel2 is created
by alias.

Test asserts:

  evsel1->core.attr.type == evsel2->core.attr.type
  evsel1->core.attr.config == evsel2->core.attr.config

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Link: http://lore.kernel.org/lkml/20210902065955.1299-3-yao.jin@linux.intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>