Avoid division in intra prediction

Avoid division in intra prediction

- Using multiplication and shifting instead of division in
  intra prediction.
- Maximum absolute difference is 1 for division statements
  in d45, d27, d63 prediction modes. However, errors can
  cumulate for large block sizes when using already predicted
  values.
- Maximum number of non-matching result values in loops using
  division are:
  4x4        0/16
  8x8        0/64
  16x16     10/256
  32x32     13/1024
  64x64    122/4096

  Overall PSNR
  derf:     0.005
  yt:      -0.022
  std-hd:   0.021
  hd:      -0.006

Change-Id: I3979a02eb6351636442c1af1e23d6c4e6ec1d01d