dt-bindings: clock: Convert brcm,bcm53573-ilp to DT schema

Convert the Broadcom BCM53573 ILP clock binding to DT schema format.
It's a straight forward conversion.

Signed-off-by: Rob Herring (Arm) <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Stephen Boyd <[e-mail]>

Documentation/devicetree/bindings/clock/brcm,bcm53573-ilp.txt

···
-Broadcom BCM53573 ILP clock
-===========================
-
-This binding uses the common clock binding:
-    Documentation/devicetree/bindings/clock/clock-bindings.txt
-
-This binding is used for ILP clock (sometimes referred as "slow clock")
-on Broadcom BCM53573 devices using Cortex-A7 CPU.
-
-ILP's rate has to be calculated on runtime and it depends on ALP clock
-which has to be referenced.
-
-This clock is part of PMU (Power Management Unit), a Broadcom's device
-handing power-related aspects. Its node must be sub-node of the PMU
-device.
-
-Required properties:
-- compatible: "brcm,bcm53573-ilp"
-- clocks: has to reference an ALP clock
-- #clock-cells: should be <0>
-- clock-output-names: from common clock bindings, should contain clock
-		      name
-
-Example:
-
-pmu@18012000 {
-	compatible = "simple-mfd", "syscon";
-	reg = <0x18012000 0x00001000>;
-
-	ilp {
-		compatible = "brcm,bcm53573-ilp";
-		clocks = <&alp>;
-		#clock-cells = <0>;
-		clock-output-names = "ilp";
-	};
-};

Documentation/devicetree/bindings/clock/brcm,bcm53573-ilp.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/brcm,bcm53573-ilp.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom BCM53573 ILP clock
+
+maintainers:
+  - Rafał Miłecki <[e-mail]>
+
+description: >
+  ILP clock (sometimes referred as "slow clock") on Broadcom BCM53573 devices
+  using Cortex-A7 CPU.
+
+  ILP's rate has to be calculated on runtime and it depends on ALP clock which
+  has to be referenced.
+
+  This clock is part of PMU (Power Management Unit), a Broadcom device handling
+  power-related aspects. Its node must be sub-node of the PMU device.
+
+properties:
+  compatible:
+    items:
+      - const: brcm,bcm53573-ilp
+
+  clocks:
+    maxItems: 1
+
+  '#clock-cells':
+    const: 0
+
+  clock-output-names:
+    items:
+      - const: ilp
+
+additionalProperties: false
+
+examples:
+  - |
+    ilp {
+        compatible = "brcm,bcm53573-ilp";
+        clocks = <&alp>;
+        #clock-cells = <0>;
+        clock-output-names = "ilp";
+    };