ARM: msm: Add devicetree support for msm8660-surf

Adds support for booting via device tree with a simple serial console.

Change-Id: I7f175b8db21928cd13e0fb49f3eed74966a2696f
Signed-off-by: David Brown <davidb@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>