iperf_api: memset entire malloc

in the function iperf_new_test
the  bitrate_limit_intervals_traffic_bytes array
was only memset for the size of the sizeof
return type, instead of the entire array.

src/iperf_api.c

@@ -2878,7 +2878,7 @@ iperf_new_test()
 	i_errno = IENEWTEST;
 	return NULL;
     }
-    memset(test->bitrate_limit_intervals_traffic_bytes, 0, sizeof(sizeof(iperf_size_t) * MAX_INTERVAL));
+    memset(test->bitrate_limit_intervals_traffic_bytes, 0, sizeof(iperf_size_t) * MAX_INTERVAL);
 
     /* By default all output goes to stdout */
     test->outfile = stdout;