MINOR: quic: Wrong largest acked packet number parsing

When we have already received ACK frames with the same largest packet
number, this is not an error at all. In this case, we must continue
to parse the ACK current frame.
diff --git a/src/xprt_quic.c b/src/xprt_quic.c
index eee13a2..7508b27 100644
--- a/src/xprt_quic.c
+++ b/src/xprt_quic.c
@@ -1511,11 +1511,11 @@
 		if (!largest_node) {
 			TRACE_DEVEL("Largest acked packet not found",
 			            QUIC_EV_CONN_PRSAFRM, ctx->conn);
-			goto err;
+		}
+		else {
+			time_sent = eb64_entry(&largest_node->node,
+			                       struct quic_tx_packet, pn_node)->time_sent;
 		}
-
-		time_sent = eb64_entry(&largest_node->node,
-		                       struct quic_tx_packet, pn_node)->time_sent;
 	}
 
 	TRACE_PROTO("ack range", QUIC_EV_CONN_PRSAFRM,