regulator: dt-bindings: samsung,s5m8767: add missing op_mode to bucks

While converting bindings to dtschema, the buck regulators lost
"op_mode" property.  The "op_mode" is a valid property for all
regulators (both LDOs and bucks), so add it.
Reported-by: Rob Herring <robh@kernel.org>
Fixes: fab58deb ("regulator: dt-bindings: samsung,s5m8767: convert to dtschema")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20211206124306.14006-1-krzysztof.kozlowski@canonical.comSigned-off-by: Mark Brown <broonie@kernel.org>

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

@@ -51,6 +51,19 @@ patternProperties:
     description:
       Properties for single BUCK regulator.
 
+    properties:
+      op_mode:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        enum: [0, 1, 2, 3]
+        default: 1
+        description: |
+          Describes the different operating modes of the regulator with power
+          mode change in SOC. The different possible values are:
+            0 - always off mode
+            1 - on in normal mode
+            2 - low power mode
+            3 - suspend mode
+
     required:
       - regulator-name
 
@@ -63,6 +76,18 @@ patternProperties:
       Properties for single BUCK regulator.
 
     properties:
+      op_mode:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        enum: [0, 1, 2, 3]
+        default: 1
+        description: |
+          Describes the different operating modes of the regulator with power
+          mode change in SOC. The different possible values are:
+            0 - always off mode
+            1 - on in normal mode
+            2 - low power mode
+            3 - suspend mode
+
       s5m8767,pmic-ext-control-gpios:
         maxItems: 1
         description: |