doc:it_IT: add some process/* translations

This patch does not translate entirely the subfolder "process/"
but only part of it (to begin with).

In order to avoid broken links, I included empty documents
for those which are not yet translated.

In order to be able to refer to all documents in "process/",
I added a sphinx label to those which had not one.

Translated documents:
- howto
- 1.Intro
- clang-format
- coding-style
- kernel-driver-statement
- magic-number
- volatile-considered-harmful
- development-process

Signed-off-by: Federico Vaga <federico.vaga@vaga.pv.it>
Signed-off-by: Alessia Mantegazza <amantegazza@vaga.pv.it>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/translations/it_IT/process/kernel-docs.rst

@@ -0,0 +1,13 @@
+.. include:: ../disclaimer-ita.rst
+
+:Original: :ref:`Documentation/process/kernel-docs.rst <kernel_docs>`
+
+
+.. _it_kernel_docs:
+
+Indice di documenti per le persone interessate a capire e/o scrivere per il kernel Linux
+========================================================================================
+
+.. warning::
+
+    TODO ancora da tradurre