[master] 8551058ef Add docs for contents of VSC_*.h

[Nils Goroll]

commit 8551058efaee216903e861a55b90948c0ce6841f
Author: Jordan Christiansen <Jordan.Christiansen at target.com>
Date:   Mon May 4 14:11:19 2020 -0500

    Add docs for contents of VSC_*.h

diff --git a/doc/sphinx/reference/vmod.rst b/doc/sphinx/reference/vmod.rst
index 6204f6684..ca448bb8e 100644
--- a/doc/sphinx/reference/vmod.rst
+++ b/doc/sphinx/reference/vmod.rst
@@ -700,3 +700,8 @@ format
 
 After these parameters, a counter can have a longer description, though
 this description has to be all on one line in the .vsc file.
+
+You should call ``VSC_*_New()`` when your VMOD is loaded and
+``VSC_*_Destroy()`` when it is unloaded. See the generated
+``VSC_*.h`` file for the full details about the structure that contains
+your counters.