docs: Move Intel Many Integrated Core documentation (mic) under misc-devices

It doesn't need to be a top-level chapter.

This patch also updates MAINTAINERS and makes sure the F: lines are
properly sorted.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200308211519.8414-1-j.neuschaefer@gmx.net


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