Replace FF_IDCT_LIBMPEG2MMX with FF_IDCT_AUTO
Replace FF_IDCT_LIBMPEG2MMX with FF_IDCT_AUTO

The former no longer exists.

Signed-off-by: Derek Buitenhuis <aff7d637ede26ea82e5226e01b697996cc52e526@gmail.com>

dwbuiten/d2vsource,dwbuiten/d2vsource