docs: Don't format internal MPT docs

This is the driver API document, so the internal stuff is just noise here.

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

docs: split up the driver book

We don't need to keep it as a single large file anymore; split it up so
that it is easier to manage and the individual sections can be read
directly as plain files.

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