fix mem leak in radio

lib/include/srslte/radio/radio.h

@@ -39,7 +39,8 @@ namespace srslte {
   */
 class radio {
  public:
-  radio() : tr_local_time(1024 * 10), tr_usrp_time(1024 * 10), tr_tx_time(1024 * 10), tr_is_eob(1024 * 10) {
+   radio() : tr_local_time(1024 * 10), tr_usrp_time(1024 * 10), tr_tx_time(1024 * 10), tr_is_eob(1024 * 10), zeros(NULL)
+   {
      bzero(&rf_device, sizeof(srslte_rf_t));
      bzero(&end_of_burst_time, sizeof(srslte_timestamp_t));
      zeros = (cf_t*)srslte_vec_malloc(burst_preamble_max_samples * sizeof(cf_t));
@@ -65,6 +66,13 @@ class radio {
      continuous_tx      = false;
   };
 
+  ~radio()
+  {
+    if (zeros) {
+      free(zeros);
+    }
+  }
+
   bool init(char *args = NULL, char *devname = NULL, uint32_t nof_channels = 1);
   void stop();
   void reset();

lib/src/radio/radio.cc

@@ -81,9 +81,6 @@ bool radio::is_init() {
 
 void radio::stop() 
 {
-  if (zeros) {
-    free(zeros);
-  }
   if (is_initialized) {
     srslte_rf_close(&rf_device);
   }