dt-bindings: arm: fsl: Add colibri-imx8x carrier boards

Prepare the dt-bindings for the new colibri-imx8x carrier-boards Aster
and Iris.

The Toradex SoM standard is called Colibri, fix the typo.

Signed-off-by: Philippe Schenker <philippe.schenker@toradex.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>