vsock: Set socket state back to SS_UNCONNECTED in vsock_connect_timeout()

vsock: Set socket state back to SS_UNCONNECTED in vsock_connect_timeout()

Imagine two non-blocking vsock_connect() requests on the same socket.
The first request schedules @connect_work, and after it times out,
vsock_connect_timeout() sets *sock* state back to TCP_CLOSE, but keeps
*socket* state as SS_CONNECTING.

Later, the second request returns -EALREADY, meaning the socket "already
has a pending connection in progress", even though the first request has
already timed out.

As suggested by Stefano, fix it by setting *socket* state back to
SS_UNCONNECTED, so that the second request will return -ETIMEDOUT.

Suggested-by: Stefano Garzarella <sgarzare@redhat.com>
Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>