dt-bindings: samsung,mipi-dsim: Add 'lane-polarities'

The Samsung DSIM IP block allows the inversion of the clock and
data lanes.

Add an optional property called 'lane-polarities' that describes the
polarities of the MIPI DSI clock and data lanes.

This property is useful for properly describing the hardware when the
board designer decided to switch the polarities of the MIPI DSI
clock and/or data lanes.

Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230514114625.98372-1-festevam@gmail.com