[alsa-lib] use /etc/asound/asound.conf instead of /etc/asound.conf

All of OpenXT uses /etc/asound/asound.conf as the main alsa config file, instead of /etc/asound.conf.
I think it is mainly due to the fact that this is the default path in the SELinux refpolicy.
The alsa deamon was not aware of that...
This should fix a lot of sound issues.