perf tracepoint: Fix memory leak in is_valid_tracepoint()

When is_valid_tracepoint() returns 1, need to call put_events_file() to
free `dir_path`.

Fixes: 25a7d91 ("perf parse-events: Use get/put_events_file()")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
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: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230421025953.173826-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: Yang Jihong

tools/perf/util/tracepoint.c

@@ -50,6 +50,7 @@ int is_valid_tracepoint(const char *event_string)
 				 sys_dirent->d_name, evt_dirent->d_name);
 			if (!strcmp(evt_path, event_string)) {
 				closedir(evt_dir);
+				put_events_file(dir_path);
 				closedir(sys_dir);
 				return 1;
 			}