QCamera2: Retreive stats debug data from previous valid frame

If the stats debug data sent from MCT is valid, then store
a copy in HAL. If during snapshot, the current frame's debug
data is not valid, then the most recent valid data which was
saved is used

Change-Id: I7f4097085d3220abe105f0a59ffbfc5c44227467
Camera: Changes to adapt to new AVTimer Driver API

A new AVTimer driver API has been provided which directly provides
the timestamp value in ticks that can be converted to appropriate
timescale and tagged to the video frames.

Change-Id: Iccb1cc4d54bb127a7ff5c303b8540edd60b3eb38
CRs-fixed: 686642
Merge "QCamera2: Retreive stats debug data from previous valid frame"
Merge "Camera: Changes to adapt to new AVTimer Driver API"