dt-bindings: display: use spi-peripheral-props.yaml

Instead of listing directly properties typical for SPI peripherals,
reference the spi-peripheral-props.yaml schema.  This allows using all
properties typical for SPI-connected devices, even these which device
bindings author did not tried yet.

Remove the spi-* properties which now come via spi-peripheral-props.yaml
schema, except for the cases when device schema adds some constraints
like maximum frequency.

While changing additionalProperties->unevaluatedProperties, put it in
typical place, just before example DTS.

The sitronix,st7735r references also panel-common.yaml and lists
explicitly allowed properties, thus here reference only
spi-peripheral-props.yaml for purpose of documenting the SPI slave
device and bringing spi-max-frequency type validation.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220727164312.385836-1-krzysztof.kozlowski@linaro.org

Documentation/devicetree/bindings/display/panel/lg,lg4573.yaml

@@ -15,13 +15,13 @@ maintainers:
 
 allOf:
   - $ref: panel-common.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
 properties:
   compatible:
     const: lg,lg4573
 
   reg: true
-  spi-max-frequency: true
 
 required:
   - compatible

Documentation/devicetree/bindings/display/sitronix,st7735r.yaml

@@ -15,6 +15,7 @@ description:
 
 allOf:
   - $ref: panel/panel-common.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
 properties:
   compatible:

Documentation/devicetree/bindings/display/solomon,ssd1307fb.yaml

@@ -49,9 +49,6 @@ properties:
   vbat-supply:
     description: The supply for VBAT
 
-  # Only required for SPI
-  spi-max-frequency: true
-
   solomon,height:
     $ref: /schemas/types.yaml#/definitions/uint32
     default: 16
@@ -153,6 +150,8 @@ required:
   - reg
 
 allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
   - if:
       properties:
         compatible:
@@ -223,7 +222,7 @@ allOf:
         solomon,dclk-frq:
           default: 10
 
-additionalProperties: false
+unevaluatedProperties: false
 
 examples:
   - |