perf test: Test pmu-events core aliases separately

The current method to test uncore event aliasing is limited, as it
relies on the uncore PMU being present in the host system to test.

As such, breakages of uncore PMU aliases goes unnoticed. To make this
more robust, a new method of testing uncore PMUs with fake PMUs will be
used in future. This will be separate to testing core PMU aliases.

So make the current test function core PMU only. Uncore PMU alias
support will be re-added later.

Signed-off-by: John Garry <john.garry@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxarm@huawei.com
Link: https //lore.kernel.org/r/1627566986-30605-6-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>