mfd: atmel-hlcdc: Add compatible for sam9x75 XLCD controller

Add compatible for sam9x75 XLCD controller.

Signed-off-by: Manikandan Muralidharan <manikandan.m@microchip.com>
Link: https://lore.kernel.org/r/20230915104849.187146-2-manikandan.m@microchip.com


Signed-off-by: Lee Jones <lee@kernel.org>