ARM: dts: imx: add devicetree for Tolino Vision 5

This adds a devicetree for the Tolino Vision 5 Ebook reader. It is
based on boards called ¨e70k02¨. It is equipped with an imx6sl SoC.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>