gnome-settings-daemon: add dependency on libsndfile

It's autodetected and leads to sstate based breakage on autobuilders:

This ends up in the package:

Package: gnome-settings-daemon
Version: 2.32.1-r3
Depends: [..] libdbus-1-3 (>= 1.4.16), libx11-6 (>= 1.4.4), libogg0 (>= 1.3.0), libsndfile1 (>= 1.0.25),

But libsndfile hasn't been built.

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>