dt-bindings: watchdog: alphascale-asm9260: convert to DT schema

Makes alphascale-asm9260 dt bindings adhere to the dt json-schema
by replacing txt file with yaml file.
Signed-off-by: Om Parikh <hack3r-0m@proton.me>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230418051446.24288-1-hack3r-0m@proton.meSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

Documentation/devicetree/bindings/watchdog/alphascale,asm9260-wdt.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/watchdog/alphascale,asm9260-wdt.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Alphascale asm9260 Watchdog timer
+
+allOf:
+  - $ref: watchdog.yaml#
+
+maintainers:
+  - Oleksij Rempel <linux@rempel-privat.de>
+
+properties:
+  compatible:
+    const: alphascale,asm9260-wdt
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: source clock, used for tick counter
+      - description: ahb gate
+
+  clock-names:
+    items:
+      - const: mod
+      - const: ahb
+
+  interrupts:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  reset-names:
+    items:
+      - const: wdt_rst
+
+  alphascale,mode:
+    description: |
+      Specifies the reset mode of operation. If set to sw, then reset is handled
+      via interrupt request, if set to debug, then it does nothing and logs.
+    $ref: /schemas/types.yaml#/definitions/string
+    enum: [hw, sw, debug]
+    default: hw
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - interrupts
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/alphascale,asm9260.h>
+    watchdog0: watchdog@80048000 {
+      compatible = "alphascale,asm9260-wdt";
+      reg = <0x80048000 0x10>;
+      clocks = <&acc CLKID_SYS_WDT>, <&acc CLKID_AHB_WDT>;
+      clock-names = "mod", "ahb";
+      interrupts = <55>;
+      timeout-sec = <30>;
+      alphascale,mode = "hw";
+    };

Documentation/devicetree/bindings/watchdog/alphascale-asm9260.txt

-Alphascale asm9260 Watchdog timer
-
-Required properties:
-
-- compatible : should be "alphascale,asm9260-wdt".
-- reg : Specifies base physical address and size of the registers.
-- clocks : the clocks feeding the watchdog timer. See clock-bindings.txt
-- clock-names : should be set to
-	"mod" - source for tick counter.
-	"ahb" - ahb gate.
-- resets : phandle pointing to the system reset controller with
-	line index for the watchdog.
-- reset-names : should be set to "wdt_rst".
-
-Optional properties:
-- timeout-sec : shall contain the default watchdog timeout in seconds,
-	if unset, the default timeout is 30 seconds.
-- alphascale,mode : three modes are supported
-	"hw" - hw reset (default).
-	"sw" - sw reset.
-	"debug" - no action is taken.
-
-Example:
-
-watchdog0: watchdog@80048000 {
-	compatible = "alphascale,asm9260-wdt";
-	reg = <0x80048000 0x10>;
-	clocks = <&acc CLKID_SYS_WDT>, <&acc CLKID_AHB_WDT>;
-	clock-names = "mod", "ahb";
-	interrupts = <55>;
-	resets = <&rst WDT_RESET>;
-	reset-names = "wdt_rst";
-	timeout-sec = <30>;
-	alphascale,mode = "hw";
-};