remove low pass filtering from two 4x4 intra prediction

In the process of developing new intra prediction modes, tests have
shown removal of the low pass filtering from B_HE_PRED and B_VE_PRED
has an overall minor positive impact in both PSNR and SSIM metric.
Overall difference is about 0.1%. The change shall also have a small
positive impact on speed. Intuitively, this change should also reduce
some of the tendency of "flattening"

Change-Id: I3c43b0daca833c6eff77d00f19c811f9ef9368a3