dt-bindings: i2c: i2c-mt7621: Add bindings for MediaTek MT7621/28/88 I2C

MediaTek MT7621/MT7628 I2C master controller

Required properties:

- compatible: Should be one of the following:

  - "mediatek,mt7621-i2c": for MT7621/MT7628/MT7688 platforms

- #address-cells: should be 1.

- #size-cells: should be 0.

- reg: Address and length of the register set for the device

- resets: phandle to the reset controller asserting this device in

          reset

  See ../reset/reset.txt for details.

Optional properties :

Example:

i2c: i2c@900 {

	compatible = "mediatek,mt7621-i2c";

	reg = <0x900 0x100>;

	#address-cells = <1>;

	#size-cells = <0>;

	resets = <&rstctrl 16>;

	reset-names = "i2c";

};