perf evsel: Fix 2 memory leaks

perf evsel: Fix 2 memory leaks

If allocated, perf_pkg_mask and metric_events need freeing.

Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200512235918.10732-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>