regulator: dt-bindings: samsung,s5m8767: Move fixed string BUCK9 to 'properties'

There's no need for a fixed string like 'BUCK9' to be under
'patternProperties', so move it under 'properties' instead.
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211221120744.1118518-1-robh@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/regulator/samsung,s5m8767.yaml

@@ -54,8 +54,9 @@ patternProperties:
     required:
       - regulator-name
 
+properties:
   # 9 buck
-  "^BUCK9$":
+  BUCK9:
     type: object
     $ref: regulator.yaml#
     unevaluatedProperties: false