subprojects: Update libgvc

This update is necessary to add support for recent UCM related changes
in ALSA and PulseAudio.

See https://gitlab.gnome.org/GNOME/libgnome-volume-control/-/merge_requests/10

https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1444
This commit is contained in:
Bastien Nocera
2020-09-21 11:06:56 +02:00
parent 0dd355543d
commit 3029119c9a