docs: parisc: convert to ReST and add to documentation body

Manually convert the two PA-RISC documents to ReST, adding them
to the Linux documentation body.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/parisc/index.rst b/Documentation/parisc/index.rst
new file mode 100644
index 0000000..aa3ee04
--- /dev/null
+++ b/Documentation/parisc/index.rst
@@ -0,0 +1,18 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+====================
+PA-RISC Architecture
+====================
+
+.. toctree::
+   :maxdepth: 2
+
+   debugging
+   registers
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`