ARM: dts: qcom: Update msm8660 device trees

* Move SoC peripherals into an SoC container node
* Move serial enabling into board file (qcom-msm8660-surf.dts)
* Cleanup cpu node to match binding spec, enable-method and compatible
  should be per cpu, not part of the container
* Add GSBI node and configuration of GSBI controller

Signed-off-by: Kumar Gala <galak@codeaurora.org>