RDMA/restrack: Change SPDX tag to properly reflect license

Resource tracking is supposed to be dual licensed: GPL-2.0 and
OpenIB, but the SPDX tag was not compliant to it. Update the tag to
properly reflect license.

Fixes: 02d8883f ("RDMA/restrack: Add general infrastructure to track RDMA resources")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/core/restrack.c

-/* SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) */
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
 /*
  * Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
  */

include/rdma/restrack.h

-/* SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) */
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
 /*
  * Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
  */