pcm: meter / s16 - add protection for the maximum copied frames
pcm: meter / s16 - add protection for the maximum copied frames

The rewind or forward may cause the stream pointer change. Although
this patch does not fix the real meter update issue, it breaks
the possible big loops when the stream pointers are desynced with
the meters. It does not make sense to copy more samples than the
pcm buffer contains.

Link: 663a2ae6da17d1068d0e9ccd3ce940eabba98e8a@ivitera.com/
Signed-off-by: Jaroslav Kysela <72edd5e1a572f82f059ccbb83c92b74d6cb051ff@perex.cz>

takaswie/alsa-lib,takaswie/alsa-lib,alsa-project/alsa-lib,tiwai/alsa-lib,tiwai/alsa-lib,tiwai/alsa-lib,takaswie/alsa-lib,takaswie/alsa-lib,tiwai/alsa-lib,alsa-project/alsa-lib,alsa-project/alsa-lib,alsa-project/alsa-lib,takaswie/alsa-lib