this patch contains the following changes:
1. added header and implemenation files of socket util apis
in libgps.utils; 2. updated XtraSystemStatusObserver to use
the new apis; 3. added HAL socket and new thread to listen to it.
Change-Id: If1f6b4b4d6ea2d03640f68e96f0286300404f42b
CRs-fixed: 2108635
