dt-bindings: arm: realtek: Add Kent Soc family compatibles

Define compatible strings for Realtek RTD1501s, RTD1861b and RTD1920s.

Additionally, convert legacy DTS-style comments to YAML description
properties, following the pattern from the ARM bindings conversion series
[1].

[1] https://lore.kernel.org/lkml/20200622125527.24207-2-afaerber@suse.de/

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20260127071530.25426-2-eleanor15x@gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Author: Yu-Chun Lin

Documentation/devicetree/bindings/arm/realtek.yaml

@@ -14,47 +14,65 @@ properties:
     const: '/'
   compatible:
     oneOf:
-      # RTD1195 SoC based boards
-      - items:
+      - description: RTD1195 SoC based boards
+        items:
           - enum:
               - mele,x1000 # MeLE X1000
               - realtek,horseradish # Realtek Horseradish EVB
           - const: realtek,rtd1195
 
-      # RTD1293 SoC based boards
-      - items:
+      - description: RTD1293 SoC based boards
+        items:
           - enum:
               - synology,ds418j # Synology DiskStation DS418j
           - const: realtek,rtd1293
 
-      # RTD1295 SoC based boards
-      - items:
+      - description: RTD1295 SoC based boards
+        items:
           - enum:
               - mele,v9 # MeLE V9
               - probox2,ava # ProBox2 AVA
               - xnano,x5 # Xnano X5
               - zidoo,x9s # Zidoo X9S
           - const: realtek,rtd1295
 
-      # RTD1296 SoC based boards
-      - items:
+      - description: RTD1296 SoC based boards
+        items:
           - enum:
               - synology,ds418 # Synology DiskStation DS418
           - const: realtek,rtd1296
 
-      # RTD1395 SoC based boards
-      - items:
+      - description: RTD1395 SoC based boards
+        items:
           - enum:
               - bananapi,bpi-m4 # Banana Pi BPI-M4
               - realtek,lion-skin # Realtek Lion Skin EVB
           - const: realtek,rtd1395
 
-      # RTD1619 SoC based boards
-      - items:
+      - description: RTD1501s SoC based boards
+        items:
+          - enum:
+              - realtek,phantom # Realtek Phantom EVB (8GB)
+          - const: realtek,rtd1501s
+
+      - description: RTD1619 SoC based boards
+        items:
           - enum:
               - realtek,mjolnir # Realtek Mjolnir EVB
           - const: realtek,rtd1619
 
+      - description: RTD1861b SoC based boards
+        items:
+          - enum:
+              - realtek,krypton # Realtek Krypton EVB (8GB)
+          - const: realtek,rtd1861b
+
+      - description: RTD1920s SoC based boards
+        items:
+          - enum:
+              - realtek,smallville # Realtek Smallville EVB (4GB)
+          - const: realtek,rtd1920s
+
 additionalProperties: true
 
 ...