staging: fsl-mc: add support for device type

The MC bus has different types of devices and this is supported by
device model. This patch adds initial support for device types
(defines them, adds helpers and sets the device type).

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>