dt-bindings: wireless: silabs,wfx: Use wireless-controller.yaml

Instead listing local-mac-address and mac-address properties, reference
wireless-controller.yaml schema. The schema brings in constraints for the
property checked during `make dtbs_check`.

Reviewed-by: Rob Herring (Arm) <[e-mail]>
Reviewed-by: Jérôme Pouiller <[e-mail]>
Signed-off-by: Janne Grunau <[e-mail]>
Signed-off-by: David Heidelberg <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Johannes Berg <[e-mail]>

Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml

···
       "Platform Data Set" in Silabs jargon). Default depends of "compatible"
       string. For "silabs,wf200", the default is 'wf200.pds'.
 
-  local-mac-address: true
-
-  mac-address: true
-
 required:
   - compatible
   - reg
 
 allOf:
+  - $ref: /schemas/net/wireless/wireless-controller.yaml#
   - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
 unevaluatedProperties: false