os: Establish new connections synchronously not on the work queue

This contortion made a bit more sense before we got SetNotifyFd and
friends, but now there's no need for it.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
1 job for less-queued-work in 1 minute and 1 second (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #43517
job

00:01:01