dt-bindings: memory-controllers: nuvoton: Add NPCM memory controller

Add dt-bindings document for Nuvoton NPCM memory controller.
Signed-off-by: Marvin Lin <milkfafa@gmail.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230111093245.318745-3-milkfafa@gmail.com

Documentation/devicetree/bindings/memory-controllers/nuvoton,npcm-memory-controller.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/memory-controllers/nuvoton,npcm-memory-controller.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Nuvoton NPCM Memory Controller
+
+maintainers:
+  - Marvin Lin <kflin@nuvoton.com>
+  - Stanley Chu <yschu@nuvoton.com>
+
+description: |
+  The Nuvoton BMC SoC supports DDR4 memory with or without ECC (error correction
+  check).
+
+  The memory controller supports single bit error correction, double bit error
+  detection (in-line ECC in which a section (1/8th) of the memory device used to
+  store data is used for ECC storage).
+
+  Note, the bootloader must configure ECC mode for the memory controller.
+
+properties:
+  compatible:
+    enum:
+      - nuvoton,npcm750-memory-controller
+      - nuvoton,npcm845-memory-controller
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    mc: memory-controller@f0824000 {
+        compatible = "nuvoton,npcm750-memory-controller";
+        reg = <0xf0824000 0x1000>;
+        interrupts = <GIC_SPI 25 IRQ_TYPE_LEVEL_HIGH>;
+    };