This makes sysupgrade work on the D-Link DIR-685 after
initial factory install.
We create the platform.sh script to support sysupgrade
on more targets as we move on with sysupgrade support.
Cc: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
[cleanup in platform.sh, removed superfluous SUPPORTED_DEVICES]
