dt-bindings: iio: proximity: vl53l0x: Add IRQ support

Since IRQ support was added to the driver, update bindings accordingly.
Signed-off-by: Ivan Drobyshevskyi <drobyshevskyi@gmail.com>
Link: https://lore.kernel.org/r/20200916074458.873359-1-drobyshevskyi@gmail.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/proximity/vl53l0x.txt

@@ -4,9 +4,15 @@ Required properties:
 	- compatible: must be "st,vl53l0x"
 	- reg: i2c address where to find the device
 
+Optional properties:
+	- interrupts:	Interrupt for notifying that new measurement is ready.
+			If no interrupt is specified, polling is used.
+
 Example:
 
 vl53l0x@29 {
 	compatible = "st,vl53l0x";
 	reg = <0x29>;
+	interrupt-parent = <&gpio>;
+	interrupts = <23 IRQ_TYPE_EDGE_FALLING>;
 };