acpi/nfit: Use the correct style for SPDX License Identifier

This patch corrects the SPDX License Identifier style in drivers/acpi/nfit/intel.h. For C header files Documentation/process/license-rules.rst mandates C-like comments (opposed to C source files where C++ style should be used)

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46

---
 drivers/acpi/nfit/intel.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 0aca682ab9d7..8f5461c1dd9d 100644
@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright(c) 2018 Intel Corporation. All rights reserved.
  * Intel specific definitions for NVDIMM Firmware Interface Table - NFIT

2.17.1