[media] v4l: Add Renesas R-Car FCP driver

The FCP is a companion module of video processing modules in the
Renesas R-Car Gen3 SoCs. It provides data compression and decompression,
data caching, and conversion of AXI transactions in order to reduce the
memory bandwidth.

The driver is not meant to be used standalone but provides an API to the
video processing modules to control the FCP.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>