perf vdso: Missed put on 32-bit dsos

If the dso type doesn't match then NULL is returned but the dso should
be put first.

Fixes: f649ed80 ("perf dsos: Tidy reference counting and locking")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240912182757.762369-1-irogers@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/vdso.c

@@ -308,8 +308,10 @@ static struct dso *machine__find_vdso(struct machine *machine,
 		if (!dso) {
 			dso = dsos__find(&machine->dsos, DSO__NAME_VDSO,
 					 true);
-			if (dso && dso_type != dso__type(dso, machine))
+			if (dso && dso_type != dso__type(dso, machine)) {
+				dso__put(dso);
 				dso = NULL;
+			}
 		}
 		break;
 	case DSO__TYPE_X32BIT: