Introduce imx6ull-colibri-u-boot.dtsi for u-boot specific properties to
keep original imx6ull-colibri.dts in sync with Linux.
Move all contents of imx6ull-colibri.dts to imx6ull-colibri.dtsi +
additionally fix checkpatch warnings.
Reviewed-by: Oleksandr Suvorov
Reviewed-by: Fabio Estevam
Signed-off-by: Igor Opaniuk