Docs/subsystem-apis: Remove '[The ]Linux' prefixes from titles of listed documents

Some documents that listed on subsystem-apis have 'Linux' or 'The Linux'
title prefixes. It's duplicated information, and makes finding the
document of interest with human eyes not easy. Remove the prefixes from
the titles.

Signed-off-by: SeongJae Park <sj@kernel.org>
Acked-by: Iwona Winiarska <iwona.winiarska@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20230122184834.181977-1-sj@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

docs: Turn off section numbering for the input docs

The input docs enable section numbering at multiple levels, leading to a
lot of bright-red "nested numbered toctree" warnings in newer Sphinx
versions. Just take that directive out for now to help alleviate the
global red-pixel shortage.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Input: docs - split input docs into kernel- and user-facing

Split input documentation into several groups: kernel- and user-facing, and
notes about individual device drivers. Move device drivers docs into a
separate subdirectory.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: docs - update joystick documentation a bit

Consolidate use instructions and userspace API notes into the same chapter;
remove completely obsolete references, move into a separate subdirectory.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: docs - remove disclaimer/GPL notice

This is just a part of kernel documentation, it does not require explicit
license notice.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: move documentation for Amiga CD32

Move the documentation for Amiga CD32 together with other parallel port
joysticks.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: create a book with Linux Input documentation

Now that all files under Documentation/input follows the ReST markup
language, rename them to *.rst and create a book for the Linux Input
subsystem.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>