[gtk/ebassi/howto-docs: 5/5] docs: Link the documentation guidelines

[Emmanuele Bassi <ebassi src gnome org>]

commit 347cb94c438149b0e68e3760af53d2768d03d551
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Wed May 27 13:44:22 2020 +0100

    docs: Link the documentation guidelines
    
    From the coding style.

 docs/CODING-STYLE.md | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/docs/CODING-STYLE.md b/docs/CODING-STYLE.md
index 36b82dced0..1867bf3fc1 100644
--- a/docs/CODING-STYLE.md
+++ b/docs/CODING-STYLE.md
@@ -759,6 +759,9 @@ To properly document a new class, it needs to be given its own section
 in the sections.txt, needs to be included in the `docs.xml` file, and the
 `get_type` function needs to listed in the `.types` file.
 
+For more information on the documentation style and contribution guidelines,
+please [follow the corresponding contribution guide](./reference/README.md).
+
 ### Old code
 
 New code that is being added to GTK should adhere to the style