Samsung MIPI DSIM bridge can also be found in i.MX8M Plus SoC.

Add dt-bingings for it.
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>