wayland: Do not fail on stalled .X11-unix entries
If for whatever reason, there are stalled files in /tmp/.X11-unix/ the bind() to the abstract socket will succeed but not the bind() to the to the UNIX socket.
This causes gnome-shell/mutter to fail because it cannot start Xwayland (while it could actually, by using a different display).
In case of failure to bind to the UNIX socket, try the next display instead of failing, to avoid stalled entries in /tmp/.X11-unix.
Closes: #13 (closed)