Whenever the RIFO buffer fill drifts away from its target, it can be
automatically reset and filled to the initial prefill_frame_count value.
The average fill is measured over several seconds. A given deviation
in percent of the prefill_frame_count is used to trigger that reset.
If the deviation is not set (0), this feature is deactivated.
There are two reasons for this to happen: The GPS clock is missing, so
the receiving interface is not in sync with the transmitting interface.
The delay changes significantly, due to congestion on the path between
both peers. (poor internet connection)
Change-Id: Id7ccbfbdb288990c01f185dec79a1022a68b4748