BUG/MINOR: quic: Missing TX packet initializations

The most important one is the ->flags member which leads to an erratic xprt behavior.
For instance a non ack-eliciting packet could be seen as ack-eliciting leading the
xprt to try to retransmit a packet which are not ack-eliciting. In this case, the
xprt does nothing and remains indefinitively in a blocking state.
diff --git a/include/haproxy/xprt_quic-t.h b/include/haproxy/xprt_quic-t.h
index e9ad911..fd6486c 100644
--- a/include/haproxy/xprt_quic-t.h
+++ b/include/haproxy/xprt_quic-t.h
@@ -524,7 +524,7 @@
 	struct eb64_node pn_node;
 	/* The list of frames of this packet. */
 	struct list frms;
-	/* The time this packet was sent (usec). */
+	/* The time this packet was sent (ms). */
 	unsigned int time_sent;
 	/* Packet number spakce. */
 	struct quic_pktns *pktns;
diff --git a/src/xprt_quic.c b/src/xprt_quic.c
index b50af85..3e4dd92 100644
--- a/src/xprt_quic.c
+++ b/src/xprt_quic.c
@@ -5299,8 +5299,10 @@
 	pkt->in_flight_len = 0;
 	pkt->pn_node.key = (uint64_t)-1;
 	LIST_INIT(&pkt->frms);
+	pkt->time_sent = TICK_ETERNITY;
 	pkt->next = NULL;
 	pkt->largest_acked_pn = -1;
+	pkt->flags = 0;
 	pkt->refcnt = 0;
 }