vp9-svc: Re-adjust some aq-mode=3 control parameters.

vp9-svc: Re-adjust some aq-mode=3 control parameters.

Remove an adjustment to two cyclic refresh (aq-mode= 3)
parameters for SVC. The adjustment was to reduce the
delta-qp on second segment, and reduce the motion threshold.
This was done early on in the SVC encoder development,
in the latest codebase removing this adjustment yields
some improvements in metrics.

The avgPSNR/SSIM metrics increase on average by ~1%
(most clip positive gain), for 3 and 2 layer SVC.

Change-Id: I7a4d5114f16b2a1df383dbe6b3fe02940e29e6cc