Tune the overrun correction

The new overrun correction is: if the previous write() cycle time is <
50% of expected, then sleep enough extra to make the total cycle time =
95% of expected.  This should help compensate for HAL implementations
that have uneven cycle times due to sample rate conversion.

Bug: 6881638
Change-Id: I5ab58afdfceee7ac523177f021fbf62d743d571a