Create socketpair and epoll. Add one end of the socketpair
to epoll and then twice send it over another end.

After restore check, that epoll can be received
via socket, and that it contains event.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>