vfio-pci/zdev: Remove repeated verbose license text

The SPDX and verbose license text are redundant, however in this case
the verbose license indicates a GPL v2 only while SPDX specifies v2+.
Remove the verbose license and correct SPDX to the more restricted
version.

Signed-off-by: Cai Huoqing <[e-mail]>
Reviewed-by: Matthew Rosato <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
[aw: commit log]
Signed-off-by: Alex Williamson <[e-mail]>

drivers/vfio/pci/vfio_pci_zdev.c

···
-// SPDX-License-Identifier: GPL-2.0+
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * VFIO ZPCI devices support
  *
  * Copyright (C) IBM Corp. 2020.  All rights reserved.
  *	Author(s): Pierre Morel <[e-mail]>
  *                 Matthew Rosato <[e-mail]>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  */
 #include <linux/io.h>
 #include <linux/pci.h>