avformat: Print error message on failure of ff_rename()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
cmdutils: Read errno before av_log() as the callback from av_log() might affect errno

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec: Read errno before av_log() as the callback from av_log() might affect errno

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avdeviece: Read errno before av_log() as the callback from av_log() might affect errno

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avfilter: Read errno before av_log() as the callback from av_log() might affect errno

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/hdsenc: Read errno before av_log() as the callback from av_log() might affect errno

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>