ucm: initialize mgr->once_list

[GitHub pull_request - opened]

alsa-project/alsa-lib pull request #50 was opened from asavah:

Initiliaze mgr->once_list otherwise eg `alsactl restore 0` will segfault in https://github.com/alsa-project/alsa-lib/blob/master/src/ucm/utils.c#L570 in case that  `/var/lib/alsa/alsa.state` is not present.

Request URL   : https://github.com/alsa-project/alsa-lib/pull/50
Patch URL     : https://github.com/alsa-project/alsa-lib/pull/50.patch
Repository URL: https://github.com/alsa-project/alsa-lib