apps/blestress: Fix tx_stress_13
We should not free mbuf in BLE_GAP_EVENT_NOTIFY_RX since it's freed by
host after returning from event callback.
@@ -1271,7 +1271,6 @@ tx_stress_13_gap_event(struct ble_gap_event *event, void *arg)
case BLE_GAP_EVENT_NOTIFY_RX:
MODLOG_DFLT(INFO, "Notify RX event\n");
console_printf("\033[0;32m>\033[0m");
- os_mbuf_free_chain(event->notify_rx.om);
++tx_stress_ctx->rcv_num;
return 0;
