dt-bindings: input: cirrus,cs40l50: Add initial DT binding

CS40L50 is a haptic driver with waveform memory,
integrated DSP, and closed-loop algorithms.

Add a YAML DT binding document for this device.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: James Ogletree <jogletre@opensource.cirrus.com>
Reviewed-by: Jeff LaBundy <jeff@labundy.com>
Link: https://lore.kernel.org/r/20240620161745.2312359-3-jogletre@opensource.cirrus.com


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