[CFL] Get subsampling from AV1 common

This change does not impact the bitstream
  PSNR | PSNR Cb | PSNR Cr | PSNR HVS |   SSIM | MS SSIM | CIEDE 2000
0.0000 |  0.0000 |  0.0000 |   0.0000 | 0.0000 |  0.0000 |     0.0000

Change-Id: I6e131e91bad5efa345ed2542ae970eb6122eff51
4 files changed