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/tcp_rules.c b/src/tcp_rules.c
index 1b48ded..564b1ea 100644
--- a/src/tcp_rules.c
+++ b/src/tcp_rules.c
@@ -103,13 +103,13 @@
 	int partial;
 	int act_flags = 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);
 
 	/* We don't know whether we have enough data, so must proceed
@@ -279,13 +279,13 @@
 	int partial;
 	int act_flags = 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,
 		rep,
 		rep->rex, rep->wex,
 		rep->flags,
-		rep->buf->i,
+		ci_data(rep),
 		rep->analysers);
 
 	/* We don't know whether we have enough data, so must proceed