ARM: dts: imx6: rename node i2c-gpio to i2c.

ARM: dts: imx6: rename node i2c-gpio to i2c.

Rename node name i2c-gpio to i2c to fix below CHECK_DTBS warnings:
arch/arm/boot/dts/nxp/imx/imx6ul-tx6ul-0010.dtb: / (karo,imx6ul-tx6ul): i2c-gpio: {'compatible': ['i2c-gpio'], '#address-cells': 1, '#size-cells': 0, 'pinctrl-names': ['default'], 'pinctrl-0': [[68]], 'sda-gpios': [[46, 1, 0]], 'scl-gpios': [[46, 0, 0]], 'clock-frequency': 400000, 'status': ['okay'], 'rtc@68': {'compatible': ['dallas,ds1339'], 'reg': [[104]], 'status': ['disabled']}} is not of type 'array'
        from schema $id: http://devicetree.org/schemas/gpio/gpio-consumer.yaml#

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>