perf test parse-events: Without a PMU use cpu-cycles rather than cycles

perf test parse-events: Without a PMU use cpu-cycles rather than cycles

Without a PMU perf matches an event against any PMU with the
event. Unfortunately some PMU drivers advertise a "cycles" event which
is typically just a core event. Switch to using "cpu-cycles" which is
an indentical legacy event but avoids the multiple PMU confusion
introduced by the PMU drivers. Note, on x86 cpu-cycles is also a sysfs
event but cycles isn't.

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: James Clark <james.clark@linaro.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>