asound.h: include <time.h> to get struct timespec prototype

without including it, we get
In file included from mixer.c:44:0:
include/sound/asound.h:337:18: error: field 'trigger_tstamp' has incomplete type
include/sound/asound.h:338:18: error: field 'tstamp' has incomplete type
etc.
1 file changed