dt-bindings: mtd: partitions: Add binding for Qcom SMEM parser

Add YAML binding for Qualcomm Shared Memory (SMEM) Flash partition
parser.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210104041137.113075-2-manivannan.sadhasivam@linaro.org

Documentation/devicetree/bindings/mtd/partitions/qcom,smem-part.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/qcom,smem-part.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm SMEM NAND flash partition parser binding
+
+maintainers:
+  - Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+
+description: |
+  The Qualcomm SoCs supporting the NAND controller interface features a Shared
+  Memory (SMEM) based partition table scheme. The maximum partitions supported
+  varies between partition table revisions. V3 supports maximum 16 partitions
+  and V4 supports 48 partitions.
+
+properties:
+  compatible:
+    const: qcom,smem-part
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    flash {
+        partitions {
+            compatible = "qcom,smem-part";
+        };
+    };