usb: gadget: f_phonet: mark expected switch fall-throughs

index 9c4c58e..710b688 100644
@@ -215,6 +215,7 @@ static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
 	case -ESHUTDOWN: /* disconnected */
 	case -ECONNRESET: /* disabled */
 		dev->stats.tx_aborted_errors++;
+		/* fall through */
 	default:
 		dev->stats.tx_errors++;
 	}

@@ -362,6 +363,7 @@ static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
 	/* Do resubmit in these cases: */
 	case -EOVERFLOW: /* request buffer overflow */
 		dev->stats.rx_over_errors++;
+		/* fall through */
 	default:
 		dev->stats.rx_errors++;
 		break;