R-Car DU MIPI DSI Encoder Support

configname: CONFIG_DRM_RCAR_USE_MIPI_DSI

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>Device Tree and Open Firmware support
└─>R-Car DU MIPI DSI Encoder Support
In linux kernel since version 6.1 (release Date: 2022-12-11)  
Enable support for the R-Car Display Unit embedded MIPI DSI encoders.