perf data: Force perf_data__open|close zero data->file.path

Making sure the data->file.path is zeroed on perf_data__open error path
and in perf_data__close, so we don't double free it in case someone call
it twice.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
Cc: Nageswara R Sastry <nasastry@in.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lkml.kernel.org/r/20190305152536.21035-9-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/data.c

@@ -237,7 +237,7 @@ static int open_file(struct perf_data *data)
 	     open_file_read(data) : open_file_write(data);
 
 	if (fd < 0) {
-		free(data->file.path);
+		zfree(&data->file.path);
 		return -1;
 	}
 
@@ -270,7 +270,7 @@ int perf_data__open(struct perf_data *data)
 
 void perf_data__close(struct perf_data *data)
 {
-	free(data->file.path);
+	zfree(&data->file.path);
 	close(data->file.fd);
 }