dt-bindings: watchdog: Fix node descriptions in uniphier-wdt example

Drop a parent node of the watchdog as it is not directly necessary.

Signed-off-by: Kunihiko Hayashi <[e-mail]>
Acked-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/watchdog/socionext,uniphier-wdt.yaml

···
   - |
     // The UniPhier watchdog should be a subnode of a "syscon" compatible node.
 
-    sysctrl@61840000 {
-        compatible = "socionext,uniphier-ld11-sysctrl",
-                     "simple-mfd", "syscon";
-        reg = <0x61840000 0x10000>;
-
-        watchdog {
-            compatible = "socionext,uniphier-wdt";
-        };
+    watchdog {
+        compatible = "socionext,uniphier-wdt";
     };