Since PVQ's max block size equals to the max transform size,
daala's definition of OD_BSIZE_MAX was changed from 5 down to 4 to
use AV1's max trasform size 32x32. However, dering also uses
OD_BSIZE_MAX and assumes its value is 5, which caused dering
not working.

Change-Id: I9d82bb24adc7d57552a8e0a8a7e798e77d96fd4b