Staging: most: add MOST driver's aim-cdev module

This patch adds the aim-cdev module of the MOST driver to the kernel's
driver staging area. This module is part of the MOST driver and handles
user space interaction by means of character devices.

This patch is needed in order to have access to MOST data through
character devices.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>