dt-bindings: arm: realtek: Tidy up conversion to json-schema

Restore the device names for compatible strings as comments.
Prepare for adding more SoCs by inserting oneOf.

Fixes: 693af5f3 ("dt-bindings: arm: Convert Realtek board/soc bindings to json-schema")
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>

Documentation/devicetree/bindings/arm/realtek.yaml

@@ -13,11 +13,12 @@ properties:
   $nodename:
     const: '/'
   compatible:
+    oneOf:
       # RTD1295 SoC based boards
-    items:
+      - items:
           - enum:
-          - mele,v9
-          - probox2,ava
-          - zidoo,x9s
+              - mele,v9 # MeLE V9
+              - probox2,ava # ProBox2 AVA
+              - zidoo,x9s # Zidoo X9S
           - const: realtek,rtd1295
 ...