ASoC: pcm030-audio-fabric: Switch to SPDX identifier

Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: Andra Danciu <andradanciu1997@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/fsl/pcm030-audio-fabric.c

-/*
- * Phytec pcm030 driver for the PSC of the Freescale MPC52xx
- * configured as AC97 interface
- *
- * Copyright 2008 Jon Smirl, Digispeaker
- * Author: Jon Smirl <jonsmirl@gmail.com>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2. This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
- */
+// SPDX-License-Identifier: GPL-2.0
+//
+// Phytec pcm030 driver for the PSC of the Freescale MPC52xx
+// configured as AC97 interface
+//
+// Copyright 2008 Jon Smirl, Digispeaker
+// Author: Jon Smirl <jonsmirl@gmail.com>
 
 #include <linux/init.h>
 #include <linux/module.h>