v1.2.15.2

Release v1.2.15.2

Core
 - Release v1.2.15.2
ALSA Control (alsactl)
 - alsactl: fix sequence to clean card specific config files for UCM
 - alsactl: add missing call to clean card specific config files
alsaloop
 - alsaloop: only log xrun debug messages when verbose
aplay/arecord
 - aplay: add support for G.711 A_LAW enconding in AU file format

Signed-off-by: Jaroslav Kysela <perex@perex.cz>