sharing: Remove vino preferences

They are unused now.
11 jobs for wip/gnome-remote-desktop in 2 minutes and 13 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #912760
build

00:01:22

 
  Test
passed #912761
test

00:00:51

 
  Manual
manual #912767
allowed to fail manual
armv8
manual #912763
allowed to fail manual
asan
manual #912762
allowed to fail manual
flatpak
manual #912766
allowed to fail manual
msan
manual #912768
allowed to fail manual
ppc64le
manual #912764
allowed to fail manual
tsan
manual #912765
allowed to fail manual
ubsan
 
  Review
manual #912769
allowed to fail manual
review
manual #912770
allowed to fail manual
stop_review