dt-bindings: can: fsl,flexcan: add optional power-domains property

Add optional power-domains property for i.MX8 usage.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/all/20230328054602.1974255-1-peng.fan@oss.nxp.comSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Documentation/devicetree/bindings/net/can/fsl,flexcan.yaml

@@ -63,6 +63,9 @@ properties:
       boot loader. This property should only be used the used operating system
       doesn't support the clocks and clock-names property.
 
+  power-domains:
+    maxItems: 1
+
   xceiver-supply:
     description: Regulator that powers the CAN transceiver.