avcodec/flac_parser: use av_freep(), do not leave stale pointers in memory

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/flac_parser: use av_freep(), do not leave stale pointers in memory

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/iirfilter: Change ff_iir_filter_free_coeffs() so it clears the pointers as well

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