Added patchlevel in OD_GNUC_PREREQ and removed redefinition.

Signed-off-by: Tristan Matthews <le.businessman@gmail.com>
odintrin: Fix include path for unix/Makefile

Signed-off-by: Tristan Matthews <le.businessman@gmail.com>
Rename mvs in od_mv_node to bma_mvs to avoid confusion

There is already an mvs in od_mv_est_ctx corresponding to the MV mesh
Fix constant velocity predictors in the BMA MC search

They're stored at full-pel resolution, not 1/8th pel.

Results on video-1-short:
           RATE (%)  DSNR (dB)
    PSNR -0.95104  0.05093
 PSNRHVS -1.44406  0.11487
    SSIM -1.25525  0.06062
FASTSSIM -1.10287  0.06805
Use round-to-even for BMA MC predictors to avoid biasing

Results on video-1-short:
           RATE (%)  DSNR (dB)
    PSNR -0.05573  0.00298
 PSNRHVS -0.06775  0.00537
    SSIM -0.05525  0.00266
FASTSSIM -0.06724  0.00412