dt-bindings: reset: microchip: Add LAN969x support

LAN969x also uses the Microchip reset driver, it reuses the LAN966x
support so use a fallback compatible.

Signed-off-by: Robert Marko <[e-mail]>
Acked-by: Conor Dooley <[e-mail]>
Signed-off-by: Philipp Zabel <[e-mail]>

Documentation/devicetree/bindings/reset/microchip,rst.yaml

···
     pattern: "^reset-controller@[0-9a-f]+$"
 
   compatible:
-    enum:
-      - microchip,sparx5-switch-reset
-      - microchip,lan966x-switch-reset
+    oneOf:
+      - enum:
+          - microchip,sparx5-switch-reset
+          - microchip,lan966x-switch-reset
+      - items:
+          - enum:
+              - microchip,lan9691-switch-reset
+          - const: microchip,lan966x-switch-reset
 
   reg:
     items: