[media] dt-bindings: media: stm32 cec driver

STMicroelectronics STM32 CEC driver

Required properties:

 - compatible : value should be "st,stm32-cec"

 - reg : Physical base address of the IP registers and length of memory

	 mapped region.

 - clocks : from common clock binding: handle to CEC clocks

 - clock-names : from common clock binding: must be "cec" and "hdmi-cec".

 - interrupts : CEC interrupt number to the CPU.

Example for stm32f746:

cec: cec@40006c00 {

	compatible = "st,stm32-cec";

	reg = <0x40006C00 0x400>;

	interrupts = <94>;

	clocks = <&rcc 0 STM32F7_APB1_CLOCK(CEC)>, <&rcc 1 CLK_HDMI_CEC>;

	clock-names = "cec", "hdmi-cec";

};