Replaces divide by 5 by a multiplication by 3/16 in the orthogonal filter
Replaces divide by 5 by a multiplication by 3/16 in the orthogonal filter

Should be faster, without affecting quality.
ntt-short1:
           RATE (%)  DSNR (dB)
    PSNR 0.01743  -0.00058
 PSNRHVS 0.01395  -0.00071
    SSIM -0.00179  0.00005
FASTSSIM -0.06009  0.00177

ycho/daala,KyleSiefring/daala,kodabb/daala,luctrudeau/daala,luctrudeau/daala,HeadhunterXamd/daala,kodabb/daala,kodabb/daala,xiphmont/daala,HeadhunterXamd/daala,HeadhunterXamd/daala,jmvalin/daala,HeadhunterXamd/daala,kodabb/daala,xiph/daala,kodabb/daala,xiph/daala,xiphmont/daala,ycho/daala,jmvalin/daala,xiph/daala,xiphmont/daala,xiph/daala,luctrudeau/daala,jmvalin/daala,luctrudeau/daala,KyleSiefring/daala,KyleSiefring/daala,ycho/daala,xiphmont/daala,jmvalin/daala,KyleSiefring/daala,ycho/daala,KyleSiefring/daala,luctrudeau/daala,xiphmont/daala,ycho/daala,HeadhunterXamd/daala,jmvalin/daala,xiph/daala