dt-bindings: arm: fsl: Add devicetree binding for Oxalis

Add devicetree binding for LS1012A SoC based Oxalis board.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>