mei: Add transport driver for IVSC device

The Intel visual sensing controller (IVSC) device is designed to control
the camera sharing between host IPU for media usage and IVSC for context
sensing (face detection).

IVSC is exposed to HOST as an SPI device and the message protocol over
the SPI BUS for communicating with the IVSC device is implemented. This
is the backend of mei framework for IVSC device, which usually handles
the hardware data transfer. The mei_csi and mei_ace are the clients of
IVSC mei framework.

The firmware downloading for the IVSC device is implemented as well.

Signed-off-by: Wentong Wu <wentong.wu@intel.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Hao Yao <hao.yao@intel.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/1701651344-20723-2-git-send-email-wentong.wu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>