ARM: BCM5301X: add dts files for BCM4708 SoC

This uses the newly added BCM5301X SoC code.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christian Daudt <bcm@fixthebug.org>
Signed-off-by: Matt Porter <mporter@linaro.org>