mei: docs: move documentation under driver-api

Move mei driver documentation under Documentation/driver-api/
Perform some minimal formating changes to produce correct sphinx rendering
and add index.rst

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
6 files changed