spi: dt-bindings: st,stm32-spi: Move "st,spi-midi-ns" to spi-peripheral-props.yaml

In order to validate SPI peripherals, SPI controller-specific child node
properties need to be in a separate schema, spi-peripheral-props.yaml,
which SPI peripheral schemas reference. As there is just a single
property in this case, just add it to spi-peripheral-props.yaml directly.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230914190049.1853136-1-robh@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml

@@ -113,6 +113,11 @@ properties:
     minItems: 2
     maxItems: 4
 
+  st,spi-midi-ns:
+    description: |
+      Only for STM32H7, (Master Inter-Data Idleness) minimum time
+      delay in nanoseconds inserted between two consecutive data frames.
+
 # The controller specific properties go here.
 allOf:
   - $ref: arm,pl022-peripheral-props.yaml#

Documentation/devicetree/bindings/spi/st,stm32-spi.yaml

@@ -18,15 +18,6 @@ maintainers:
 
 allOf:
   - $ref: spi-controller.yaml#
-  - if:
-      properties:
-        compatible:
-          contains:
-            const: st,stm32f4-spi
-
-    then:
-      properties:
-        st,spi-midi-ns: false
 
 properties:
   compatible:
@@ -59,17 +50,6 @@ properties:
       - const: rx
       - const: tx
 
-patternProperties:
-  "^[a-zA-Z][a-zA-Z0-9,+\\-._]{0,63}@[0-9a-f]+$":
-    type: object
-    # SPI slave nodes must be children of the SPI master node and can
-    # contain the following properties.
-    properties:
-      st,spi-midi-ns:
-        description: |
-          Only for STM32H7, (Master Inter-Data Idleness) minimum time
-          delay in nanoseconds inserted between two consecutive data frames.
-
 required:
   - compatible
   - reg