CLEANUP: listener: replace bind_conf->quic_force_retry with BC_O_QUIC_FORCE_RETRY

It was only set and used once, let's replace it now and take it out of
the ifdef.
diff --git a/src/cfgparse-quic.c b/src/cfgparse-quic.c
index 03f4178..db637e0 100644
--- a/src/cfgparse-quic.c
+++ b/src/cfgparse-quic.c
@@ -7,7 +7,7 @@
 
 static int bind_parse_quic_force_retry(char **args, int cur_arg, struct proxy *px, struct bind_conf *conf, char **err)
 {
-	conf->quic_force_retry = 1;
+	conf->options |= BC_O_QUIC_FORCE_RETRY;
 	return 0;
 }