linux-imx

of: documentation: add bindings documentation for TS-4800

This adds the documentation for the TS-4800 by Technologic Systems.

Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>