vp3: bfin: Transpose the IDCTs

While this change isn't bitexact, the IDCTs weren't bitexact to
start with either.

This simplifies decoupling vp3 from dsputil.
vp3: Use full transpose for all IDCTs

This way, the special IDCT permutations are no longer needed. This
is similar to how H264 does it, and removes the dsputil dependency
imposed by the scantable code.

Also remove the unused type == 0 cases from the plain C version
of the idct.
hpeldsp: Add half-pel functions (currently copies of dsputil)
vp3: Use hpeldsp instead of dsputil for half-pel functions

This makes vp3 independent of dsputil.
vp56: Use hpeldsp instead of dsputil for half-pel functions

This makes vp5 and vp6 independent of dsputil.
indeo3: Use hpeldsp instead of dsputil for half-pel functions

This makes the Indeo 3 decoder independent of dsputil.
bink: Use hpeldsp instead of dsputil for half-pel functions
interplayvideo: Use hpeldsp instead of dsputil for half-pel functions

This makes interplayvideo independent of dsputil.
mimic: Use hpeldsp instead of dsputil for half-pel functions
svq1: Use hpeldsp instead of dsputil for half-pel functions

This makes svq1 independent of dsputil.
mpegvideo: Use hpeldsp instead of dsputil for half-pel functions

This also converts vc1, since that is mpegvideo-based.
svq3: Use hpeldsp instead of dsputil for half-pel functions
svq1enc: Use hpeldsp instead of dsputil for half-pel functions
mjpeg: Use hpeldsp instead of dsputil for half-pel functions
x86: hpeldsp: Move half-pel assembly from dsputil to hpeldsp
ppc: hpeldsp: Move half-pel assembly from dsputil to hpeldsp
arm: hpeldsp: Move half-pel assembly from dsputil to hpeldsp
bfin: hpeldsp: Move half-pel assembly from dsputil to hpeldsp
sh4: hpeldsp: Move half-pel assembly from dsputil to hpeldsp
sparc: hpeldsp: Move vis half-pel assembly from dsputil to hpeldsp