dt-bindings: clock: Convert i.MX21 clock to json-schema

* Clock bindings for Freescale i.MX21

Required properties:

- compatible  : Should be "fsl,imx21-ccm".

- reg         : Address and length of the register set.

- interrupts  : Should contain CCM interrupt.

- #clock-cells: Should be <1>.

The clock consumer should specify the desired clock by having the clock

ID in its "clocks" phandle cell. See include/dt-bindings/clock/imx21-clock.h

for the full list of i.MX21 clock IDs.

Examples:

	clks: ccm@10027000{

		compatible = "fsl,imx21-ccm";

		reg = <0x10027000 0x800>;

		#clock-cells = <1>;

	};

	uart1: serial@1000a000 {

		compatible = "fsl,imx21-uart";

		reg = <0x1000a000 0x1000>;

		interrupts = <20>;

		clocks = <&clks IMX21_CLK_UART1_IPG_GATE>,

			 <&clks IMX21_CLK_PER1>;

		clock-names = "ipg", "per";

	};

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

%YAML 1.2

---

$id: http://devicetree.org/schemas/clock/imx21-clock.yaml#

$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Clock bindings for Freescale i.MX21

maintainers:

  - Alexander Shiyan <shc_work@mail.ru>

description: |

  The clock consumer should specify the desired clock by having the clock

  ID in its "clocks" phandle cell. See include/dt-bindings/clock/imx21-clock.h

  for the full list of i.MX21 clock IDs.

properties:

  compatible:

    const: fsl,imx21-ccm

  reg:

    maxItems: 1

  '#clock-cells':

    const: 1

required:

  - compatible

  - reg

  - '#clock-cells'

additionalProperties: false

examples:

  - |

    #include <dt-bindings/clock/imx21-clock.h>

    clock-controller@10027000 {

        compatible = "fsl,imx21-ccm";

        reg = <0x10027000 0x800>;

        #clock-cells = <1>;

    };

    serial@1000a000 {

        compatible = "fsl,imx21-uart";

        reg = <0x1000a000 0x1000>;

        interrupts = <20>;

        clocks = <&clks IMX21_CLK_UART1_IPG_GATE>,

                 <&clks IMX21_CLK_PER1>;

        clock-names = "ipg", "per";

    };