BUG/MIONR: quic: fix fc_lost

Control layer callback get_info has recently been implemented for QUIC.
However, fc_lost always returned 0. This is because quic_get_info() does
not use the correct input argument value to identify lost value.

This does not need to be backported.

src/proto_quic.c

@@ -704,7 +704,7 @@ static int quic_get_info(struct connection *conn, long long int *info, int info_
 	switch (info_num) {
 	case 0:  *info = qc->path->loss.srtt * 1000;      break;
 	case 1:  *info = qc->path->loss.rtt_var * 1000;   break;
-	case 3:  *info = qc->path->loss.nb_lost_pkt;      break;
+	case 4:  *info = qc->path->loss.nb_lost_pkt;      break;
 	case 7:  *info = qc->path->loss.nb_reordered_pkt; break;
 	default: return 0;
 	}