[4.1] 7e88396 Make documentation reference more explicit

[Dridi Boukelmoune]

commit 7e883962c0bf065d54ab22dbfa88d9da19546a37
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Tue Aug 11 17:49:53 2015 +0200

    Make documentation reference more explicit

diff --git a/doc/sphinx/reference/vmod.rst b/doc/sphinx/reference/vmod.rst
index 57fea73..387843a 100644
--- a/doc/sphinx/reference/vmod.rst
+++ b/doc/sphinx/reference/vmod.rst
@@ -193,16 +193,16 @@ STRING_LIST
 	are big enough.
 
 PRIV_VCL
-	See below
+	See :ref:`ref-vmod-private-pointers` below
 
 PRIV_CALL
-	See below
+	See :ref:`ref-vmod-private-pointers` below
 
 PRIV_TASK
-	See below
+	See :ref:`ref-vmod-private-pointers` below
 
 PRIV_TOP
-	See below
+	See :ref:`ref-vmod-private-pointers` below
 
 VOID
 	C-type: ``void``
@@ -240,6 +240,8 @@ BLOB
 	functions.
 
 
+.. _ref-vmod-private-pointers:
+
 Private Pointers
 ================