resample: implement flushing
FATE: add tests for more resampling modes
lavr: allocate the resampling buffer with a positive size

This fixes cases where very few input samples (fewer than needed for one
output sample) are passed to lavr at the beginning.
CC:libav-stable@libav.org
af_volume: implement replaygain clipping prevention

This adds a new "replaygain_noclip" option to the filter, and, if enabled,
limits the gain applied for tracks where clipping would occur.

Signed-off-by: Anton Khirnov <anton@khirnov.net>
x86/synth_filter: remove the fma3 version ifdefs

This fixes compilation failures with --disable-fma3

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>