Request body: commented out debug printing of old buffers.

This is not really needed in practice, and causes excessive debug output
in some of our tests.

src/http/ngx_http_request_body.c

diff --git a/src/http/ngx_http_request_body.c b/src/http/ngx_http_request_body.c
index d84dbf8..2f66484 100644
--- a/src/http/ngx_http_request_body.c
+++ b/src/http/ngx_http_request_body.c
@@ -1087,6 +1087,7 @@
 
 #if (NGX_DEBUG)
 
+#if 0
     for (cl = rb->bufs; cl; cl = cl->next) {
         ngx_log_debug7(NGX_LOG_DEBUG_EVENT, r->connection->log, 0,
                        "http body old buf t:%d f:%d %p, pos %p, size: %z "
@@ -1097,6 +1098,7 @@
                        cl->buf->file_pos,
                        cl->buf->file_last - cl->buf->file_pos);
     }
+#endif
 
     for (cl = in; cl; cl = cl->next) {
         ngx_log_debug7(NGX_LOG_DEBUG_EVENT, r->connection->log, 0,