av_seek_frame_binary, just as they do in av_seek_frame_generic.
Otherwise, function may return success even though url_fseek reported
failure.

Patch by Sean Soria, first.last at gmail



git-svn-id: file:///var/local/repositories/ffmpeg/trunk@20744 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b