VSOCK: add SPDX identifiers to vsock tests

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/vsock/control.h

+/* SPDX-License-Identifier: GPL-2.0-only */
 #ifndef CONTROL_H
 #define CONTROL_H
 

tools/testing/vsock/timeout.h

+/* SPDX-License-Identifier: GPL-2.0-only */
 #ifndef TIMEOUT_H
 #define TIMEOUT_H