ARM: dts: add SMSC ethernet on the APQ8060 Dragonboard

The SMSC9112 ethernet controller is connected to chip select 2
on the EBI2 bus on the APQ8060 Dragonboard. We set this up by
activating EBI2, creating a chipselect entry as a subnode, and then
putting the ethernet controller in a subnode of the chipselect.

After the chipselect is configured, the SMSC device will be
instantiated.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>