dt-bindings: input: atmel,captouch: convert bindings to YAML

Convert the Atmel capacitive touchscreen bindings to YAML format.

Signed-off-by: Dharma Balasubiramani <dharma.b@microchip.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240209064755.47516-1-dharma.b@microchip.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>