BUG/MINOR: build: Fix compilation with debug mode enabled

It remained some fragments of the old buffers API in debug messages, here and
there.

This was caused by the recent buffer API changes, no backport is needed.
diff --git a/src/proto_http.c b/src/proto_http.c
index 56035b9..6fa38dd 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -1613,13 +1613,13 @@
 	struct http_msg *msg = &txn->req;
 	struct hdr_ctx ctx;
 
-	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%d analysers=%02x\n",
+	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%lu analysers=%02x\n",
 		now_ms, __FUNCTION__,
 		s,
 		req,
 		req->rex, req->wex,
 		req->flags,
-		req->buf.i,
+		ci_data(req),
 		req->analysers);
 
 	/* we're speaking HTTP here, so let's speak HTTP to the client */
@@ -3477,13 +3477,13 @@
 		goto return_prx_yield;
 	}
 
-	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%d analysers=%02x\n",
+	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%lu analysers=%02x\n",
 		now_ms, __FUNCTION__,
 		s,
 		req,
 		req->rex, req->wex,
 		req->flags,
-		req->buf.i,
+		ci_data(req),
 		req->analysers);
 
 	/* just in case we have some per-backend tracking */
@@ -3749,13 +3749,13 @@
 		return 0;
 	}
 
-	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%d analysers=%02x\n",
+	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%lu analysers=%02x\n",
 		now_ms, __FUNCTION__,
 		s,
 		req,
 		req->rex, req->wex,
 		req->flags,
-		req->buf.i,
+		ci_data(req),
 		req->analysers);
 
 	/*
@@ -4909,13 +4909,13 @@
 	struct http_msg *msg = &s->txn->req;
 	int ret;
 
-	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%d analysers=%02x\n",
+	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%lu analysers=%02x\n",
 		now_ms, __FUNCTION__,
 		s,
 		req,
 		req->rex, req->wex,
 		req->flags,
-		req->buf.i,
+		ci_data(req),
 		req->analysers);
 
 	if (unlikely(msg->msg_state < HTTP_MSG_BODY))
@@ -5145,7 +5145,7 @@
 	int cur_idx;
 	int n;
 
-	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%d analysers=%02x\n",
+	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%lu analysers=%02x\n",
 		now_ms, __FUNCTION__,
 		s,
 		rep,
@@ -5777,7 +5777,7 @@
 	struct cond_wordlist *wl;
 	enum rule_result ret = HTTP_RULE_RES_CONT;
 
-	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%d analysers=%02x\n",
+	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%lu analysers=%02x\n",
 		now_ms, __FUNCTION__,
 		s,
 		rep,
@@ -6126,13 +6126,13 @@
 	struct http_msg *msg = &s->txn->rsp;
 	int ret;
 
-	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%d analysers=%02x\n",
+	DPRINTF(stderr,"[%u] %s: stream=%p b=%p, exp(r,w)=%u,%u bf=%08x bh=%lu analysers=%02x\n",
 		now_ms, __FUNCTION__,
 		s,
 		res,
 		res->rex, res->wex,
 		res->flags,
-		res->buf.i,
+		ci_data(res),
 		res->analysers);
 
 	if (unlikely(msg->msg_state < HTTP_MSG_BODY))