Enable 32x32 dct tests

Also
1. Removed the test code for fDCT from the iDCT test.
2. changed the criteria of round trip error to be below 1/block, this
is quite strict comparing to smaller transforms when size differences
are accounted for.

Change-Id: Idb46a6380b04c93fc8e2845c75f5a850366b0090
2 files changed