[VLC 3] build failure due to libplacebo change
On VLC3, build fails on this line: https://code.videolan.org/videolan/vlc/-/blob/7d014e8d4b7a911a0d823075658d3ea390ddf5dc/modules/video_output/opengl/vout_helper.c#L637
because caps has been removed from pl_gpu_dummy_params in libplacebo by this commit: https://github.com/haasn/libplacebo/commit/2d0786d1fc8e7e30243c5ab5b49adafc3664ebdf