Backport upstream patch to drop openh264 runtime version checks
    
    ... in order to make it possible for us to update openh264 without
    having to recompile ffmpeg against the new version every time. As
    openh264 is distributed by Cisco and ffmpeg is in Fedora, it's difficult
    to coordinate lock step updates. Drop the version check to make this
    easier.
    
    https://patchwork.ffmpeg.org/project/ffmpeg/list/?series=10211
    
    This also rebases downstream ffmpeg-dlopen-openh264.patch on top of
    the new patch.