lavfi: switch ff_default_get_audio_buffer() to av_frame_get_buffer()

This simplifies the code and avoids using libavcodec-specific
avcodec_fill_audio_frame().
configure: Remove unneeded icl inline compatibility definition

Signed-off-by: Martin Storsjö <martin@martin.st>
vsrc_movie: do not free avoption variables in uninit()

The generic code frees them as well. Since av_free was used to free them
instead of av_freep, this would result in a double free.
lavc: free the padded last frame during audio encoding properly
dynamic loading of shared faac library
no Werror on implicit-function-declaration and missing-prototypes
custom icon and windows resource
use upstream version tag, my repo is always rebased