cifs: call wake_up(&server->response_q) inside of cifs_reconnect()

This means it's consistently called and the callers don't need to
care about it.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>