ffmpeg: Bump to n2.4.3
Fix for channel count when using request_channel_layout with TrueHD
Exit when seeking beyond end of file

See: https://github.com/popcornmix/omxplayer/issues/270
Always enable the timestamp fifo mode and let the GPU choose

See: https://github.com/popcornmix/omxplayer/issues/264
Remove spammy log message from Keyboard
Fix for chapter seeks