video: mxsfb: add support for i.MXRT

Add support for i.MXRT by adding CONFIG_IMXRT in register structure and
adding .compatible = "fsl,imxrt-lcdif".

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
3 files changed