dt_bindings: mtd: partitions: redboot: convert to YAML

Converts mtd/partitions/redboot-fis.txt to YAML.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@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/20210628191440.2823024-1-clabbe@baylibre.com

Documentation/devicetree/bindings/mtd/partitions/redboot-fis.txt

-RedBoot FLASH Image System (FIS) Partitions
-===========================================
-
-The FLASH Image System (FIS) directory is a flash description
-format closely associated with the RedBoot boot loader.
-
-It uses one single flash eraseblock in the flash to store an index of
-all images in the flash.
-
-This block size will vary depending on flash but is typically
-32 KB in size.
-
-Required properties:
-- compatible : (required) must be "redboot-fis"
-- fis-index-block : (required) a index to the eraseblock containing
-  the FIS directory on this device. On a flash memory with 32KB
-  eraseblocks, 0 means the first eraseblock at 0x00000000, 1 means the
-  second eraseblock at 0x00008000 and so on.
-
-Example:
-
-flash@0 {
-	partitions {
-		compatible = "redboot-fis";
-		fis-index-block = <0>;
-	};
-};

Documentation/devicetree/bindings/mtd/partitions/redboot-fis.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/redboot-fis.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RedBoot FLASH Image System (FIS) Partitions
+
+description: The FLASH Image System (FIS) directory is a flash description
+    format closely associated with the RedBoot boot loader.
+    It uses one single flash eraseblock in the flash to store an index of
+    all images in the flash.
+    This block size will vary depending on flash but is typically
+    32 KB in size.
+
+maintainers:
+  - Linus Walleij <linus.walleij@linaro.org>
+
+properties:
+  compatible:
+    const: redboot-fis
+
+  fis-index-block:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: a index to the eraseblock containing the FIS directory on this
+      device. On a flash memory with 32KB eraseblocks, 0 means the first
+      eraseblock at 0x00000000, 1 means the second eraseblock at 0x00008000 and so on.
+
+required:
+  - compatible
+  - fis-index-block
+
+additionalProperties: false
+
+examples:
+  - |
+    flash {
+      partitions {
+        compatible = "redboot-fis";
+        fis-index-block = <0>;
+      };
+    };