staging: wlan-ng: add SPDX identifiers to all wlan-ng driver files

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the wlan-ng driver files with the correct SPDX license identifier
based on the license text in the file itself.  The SPDX identifier is a
legally binding shorthand, which can be used instead of the full boiler
plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/wlan-ng/prism2mgmt.c b/drivers/staging/wlan-ng/prism2mgmt.c
index 7207059..78934e4 100644
--- a/drivers/staging/wlan-ng/prism2mgmt.c
+++ b/drivers/staging/wlan-ng/prism2mgmt.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MPL-1.1)
 /* src/prism2/driver/prism2mgmt.c
  *
  * Management request handler functions.