doc:process: add links where missing

Some documents are refering to others without links. With this
patch I add those missing links.

This patch affects only documents under process/ and labels where
necessary.

Signed-off-by: Federico Vaga <federico.vaga@vaga.pv.it>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst
index 4e7c0a1..277c113 100644
--- a/Documentation/process/coding-style.rst
+++ b/Documentation/process/coding-style.rst
@@ -1075,5 +1075,5 @@
 WG14 is the international standardization working group for the programming
 language C, URL: http://www.open-std.org/JTC1/SC22/WG14/
 
-Kernel process/coding-style.rst, by greg@kroah.com at OLS 2002:
+Kernel :ref:`process/coding-style.rst <codingstyle>`, by greg@kroah.com at OLS 2002:
 http://www.kroah.com/linux/talks/ols_2002_kernel_codingstyle_talk/html/