* commit '85770f2a':
  AVOptions: make default_val a union, as proposed in AVOption2.
  Move ff_dynarray_add to lavu and make it public.
  lavf: remove duplicate assignment in avformat_alloc_context.
  lavf: use designated initializers for AVClasses.
  options: simplify av_find_opt by using av_next_option.
Merged-by: Michael Niedermayer <michaelni@gmx.at>