dt-bindings: arm: renesas: Document Renesas RZ/V2M System Configuration

Add DT binding documentation for System Configuration (SYS) found on
RZ/V2M SoC's.

SYS block contains the SYS_VERSION register which can be used to retrieve
SoC version information.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221116102140.852889-2-biju.das.jz@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Documentation/devicetree/bindings/soc/renesas/renesas,r9a09g011-sys.yaml

@@ -0,0 +1,43 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/soc/renesas/renesas,r9a09g011-sys.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas RZ/V2M System Configuration (SYS)
+
+maintainers:
+  - Geert Uytterhoeven <geert+renesas@glider.be>
+
+description:
+  The RZ/V2M-alike SYS (System Configuration) controls the overall
+  configuration of the LSI and supports the following functions,
+  - Bank address settings for DMAC
+  - Bank address settings of the units for ICB
+  - ETHER AxCACHE[1] (C bit) control function
+  - RAMA initialization control
+  - MD[7:0] pin monitoring
+  - LSI version
+  - PCIe related settings
+  - WDT stop control
+  - Temperature sensor (TSU) monitor
+
+properties:
+  compatible:
+    const: renesas,r9a09g011-sys
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    sys: system-controller@a3f03000 {
+      compatible = "renesas,r9a09g011-sys";
+      reg = <0xa3f03000 0x400>;
+    };