ARM: dts: add devicetree entry for Tolino Shine 3

The device is almost identical to the Kobo Clara HD. The only
spotted difference is the SoC. It contains an imx6sl
instead of an imx6sll.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>