perf test session_topology: Delete session->evlist

ASan reports a memory leak related to session->evlist while running:

  # perf test "41: Session topology".

When perf_data is in write mode, session->evlist is owned by the caller,
which should also take care of deleting it.

This patch adds the missing evlist__delete().

Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Fixes: c84974ed

 ("perf test: Add entry to test cpu topology")
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/822f741f06eb25250fb60686cf30a35f447e9e91.1626343282.git.rickyman7@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>