dt-bindings: mmc: renesas,sdhi: Fix dtbs-check warning

Fix dtbs-check warning pinctrl-names:0:'default' was expected
for r8a77470-iwg23s-sbc.dts file.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210817090313.31858-2-biju.das.jz@bp.renesas.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml

@@ -9,9 +9,6 @@ title: Renesas SDHI SD/MMC controller
 maintainers:
   - Wolfram Sang <wsa+renesas@sang-engineering.com>
 
-allOf:
-  - $ref: "mmc-controller.yaml"
-
 properties:
   compatible:
     oneOf:
@@ -104,14 +101,46 @@ properties:
   pinctrl-1:
     maxItems: 1
 
-  pinctrl-names:
-    minItems: 1
-    items:
-      - const: default
-      - const: state_uhs
+  pinctrl-names: true
 
   max-frequency: true
 
+allOf:
+  - $ref: "mmc-controller.yaml"
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: renesas,sdhi-mmc-r8a77470
+    then:
+      properties:
+        pinctrl-names:
+          items:
+            - const: state_uhs
+    else:
+      properties:
+        pinctrl-names:
+          minItems: 1
+          items:
+            - const: default
+            - const: state_uhs
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - renesas,sdhi-r7s72100
+              - renesas,sdhi-r7s9210
+    then:
+      required:
+        - clock-names
+      description:
+        The internal card detection logic that exists in these controllers is
+        sectioned off to be run by a separate second clock source to allow
+        the main core clock to be turned off to save power.
+
 required:
   - compatible
   - reg
@@ -119,21 +148,6 @@ required:
   - clocks
   - power-domains
 
-if:
-  properties:
-    compatible:
-      contains:
-        enum:
-          - renesas,sdhi-r7s72100
-          - renesas,sdhi-r7s9210
-then:
-  required:
-    - clock-names
-  description:
-    The internal card detection logic that exists in these controllers is
-    sectioned off to be run by a separate second clock source to allow
-    the main core clock to be turned off to save power.
-
 unevaluatedProperties: false
 
 examples: