MINOR: dynbuf: use regular lists instead of mt_lists for buffer_wait

There's no point anymore in keeping mt_lists for the buffer_wait and
buffer_wq since it's thread-local now.

(cherry picked from commit 90f366b59556f9e64c927286bfc8e9c06d511744)
Signed-off-by: Willy Tarreau <w@1wt.eu>
diff --git a/src/mux_h2.c b/src/mux_h2.c
index 7fcade5..9272ae4 100644
--- a/src/mux_h2.c
+++ b/src/mux_h2.c
@@ -798,11 +798,11 @@
 {
 	struct buffer *buf = NULL;
 
-	if (likely(!MT_LIST_ADDED(&h2c->buf_wait.list)) &&
+	if (likely(!LIST_ADDED(&h2c->buf_wait.list)) &&
 	    unlikely((buf = b_alloc_margin(bptr, 0)) == NULL)) {
 		h2c->buf_wait.target = h2c;
 		h2c->buf_wait.wakeup_cb = h2_buf_available;
-		MT_LIST_ADDQ(&ti->buffer_wq, &h2c->buf_wait.list);
+		LIST_ADDQ(&ti->buffer_wq, &h2c->buf_wait.list);
 	}
 	return buf;
 }
@@ -979,7 +979,7 @@
 	LIST_INIT(&h2c->send_list);
 	LIST_INIT(&h2c->fctl_list);
 	LIST_INIT(&h2c->blocked_list);
-	MT_LIST_INIT(&h2c->buf_wait.list);
+	LIST_INIT(&h2c->buf_wait.list);
 
 	conn->ctx = h2c;
 
@@ -1066,8 +1066,8 @@
 		TRACE_DEVEL("freeing h2c", H2_EV_H2C_END, conn);
 		hpack_dht_free(h2c->ddht);
 
-		if (MT_LIST_ADDED(&h2c->buf_wait.list))
-			MT_LIST_DEL(&h2c->buf_wait.list);
+		if (LIST_ADDED(&h2c->buf_wait.list))
+			LIST_DEL_INIT(&h2c->buf_wait.list);
 
 		h2_release_buf(h2c, &h2c->dbuf);
 		h2_release_mbuf(h2c);