dt-bindings: fuse: Document R-Car E-FUSE / OTP_MEM

Document support for E-FUSE non-volatile memory accessible through
OTP_MEM on R-Car V4H and V4M.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/436506babe4ce468fda19380d9373470468e3752.1716974502.git.geert+renesas@glider.be

Documentation/devicetree/bindings/fuse/renesas,rcar-otp.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/fuse/renesas,rcar-otp.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: R-Car E-FUSE connected to OTP_MEM
+
+maintainers:
+  - Geert Uytterhoeven <geert+renesas@glider.be>
+
+description:
+  The E-FUSE is a type of non-volatile memory, which is accessible through the
+  One-Time Programmable Memory (OTP_MEM) module on some R-Car Gen4 SoCs.
+
+properties:
+  compatible:
+    enum:
+      - renesas,r8a779g0-otp # R-CarV4H
+      - renesas,r8a779h0-otp # R-CarV4M
+
+  reg:
+    items:
+      - description: OTP_MEM_0
+      - description: OTP_MEM_1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    otp: otp@e61be000 {
+            compatible = "renesas,r8a779g0-otp";
+            reg = <0xe61be000 0x1000>, <0xe61bf000 0x1000>;
+    };