conf: Add /usr/etc to the default search paths
conf: Add /usr/etc to the default search paths

There's been some recent action to move the distribution-default setup
from /etc to /usr/etc, and we should follow that, too.

This patch adds /usr/etc/alsa.conf.d and /usr/etc/alsa.conf to the
default search paths.

Signed-off-by: Takashi Iwai <4596b3305151c7ee743192a95d394341e3d3b644@suse.de>

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