dt: bindings: lp55xx: Updte yaml examples with new color ID

Update the binding examples for the color ID to LED_COLOR_ID_RGB

Signed-off-by: Dan Murphy <[e-mail]>
Acked-by: Rob Herring <[e-mail]>
Signed-off-by: Pavel Machek <[e-mail]>

Documentation/devicetree/bindings/leds/leds-lp55xx.yaml

···
                #address-cells = <1>;
                #size-cells = <0>;
                reg = <0x2>;
-               color = <LED_COLOR_ID_MULTI>;
+               color = <LED_COLOR_ID_RGB>;
                function = LED_FUNCTION_STANDBY;
                linux,default-trigger = "heartbeat";