Plain C, x86-32 and -64 have been tested and should work, other
archs that had asm optmizations in swscale likely will need some fixes
to either fallback to C if SWS_BITEXACT is set or make the asm match C.
This also disables the PAL8 test as neither swscale or the old scaler
really support PAL8 output, imgconvert supported a fixed 666 palette
as output and swscale supports fixed 884 and 422.


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@15305 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b