Fix build on ppc64 / clang. Details: - Import build fix from upstream, see: https://ffmpeg.org/pipermail/ffmpeg-devel/2019-August/247682.html https://trac.ffmpeg.org/ticket/7861 PR: 239782 Submitted by: pkubaj
head/multimedia/ffmpeg/files/patch-libswscale_ppc_swscale__altivec.c