dt-bindings: mtd: partitions: Move "sercomm,scpart-id" to partition.yaml

Defining child node properties specific to the parent schema doesn't work
unless all the child node properties are known. They aren't known because
any partition can define its own properties. The solution to this is
typically something like spi-peripheral-props.yaml, but that's overkill for
this single property. Just move it to partition.yaml instead.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Documentation/devicetree/bindings/mtd/partitions/partition.yaml

@@ -126,6 +126,15 @@ properties:
       - xz
       - zstd
 
+  sercomm,scpart-id:
+    description: Partition id in Sercomm partition map. Mtd parser
+      uses this id to find a record in the partition map containing
+      offset and size of the current partition. The values from
+      partition map overrides partition offset and size defined in
+      reg property of the dts. Frequently these values are the same,
+      but may differ if device has bad eraseblocks on a flash.
+    $ref: /schemas/types.yaml#/definitions/uint32
+
 if:
   not:
     required: [ reg ]