ccn-lite: shell: free all memory, not just prefix struct

sys/shell/commands/sc_ccnl.c

@@ -226,7 +226,7 @@ int _ccnl_interest(int argc, char **argv)
             printf("Content received: %s\n", _cont_buf);
             return 0;
         }
-        ccnl_free(prefix);
+        free_prefix(prefix);
         gnrc_netreg_unregister(GNRC_NETTYPE_CCN_CHUNK, &_ne);
     }
     printf("Timeout! No content received in response to the Interest for %s.\n", argv[1]);