This commit fixes the 2x2 transform system setups for high bit-
depth setting. It enables the cb4x4 mode to support high bit-depth
process. The coding performance is improved over high bit-depth +
ref-mv:

lowres  2.5%
midres  1.2%

Change-Id: I351f9d72bdc7e15b2bd00e94286b98966a295e6d