ASoC: fix NULL pointer dereference in soc_suspend()

In case the initalization of an soc_device failed, there is no codec
associated with it. soc_suspend() will still dereference the pointer
and cause an Ooops when entering the sleep mode.

This happens on our board with a multi-target kernel image when booted
on a machine without audio circuits.

This patch makes the code bail out very early in this special case.
Signed-off-by: NDaniel Mack <daniel@caiaq.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/soc-core.c

@@ -628,6 +628,12 @@ static int soc_suspend(struct platform_device *pdev, pm_message_t state)
 	struct snd_soc_codec *codec = card->codec;
 	int i;
 
+	/* If the initialization of this soc device failed, there is no codec
+	 * associated with it. Just bail out in this case.
+	 */
+	if (!codec)
+		return 0;
+
 	/* Due to the resume being scheduled into a workqueue we could
 	* suspend before that's finished - wait for it to complete.
 	 */