[ALSA] ASoC AC97 static GPL symbol fix

This patch fixes a bug whereby the GPL'ed symbol ac97_dai was being
declared as static.
Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

sound/soc/codecs/ac97.c

@@ -43,7 +43,7 @@ static int ac97_prepare(struct snd_pcm_substream *substream)
 #define STD_AC97_RATES (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |\
 		SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000)
 
-static struct snd_soc_codec_dai ac97_dai = {
+struct snd_soc_codec_dai ac97_dai = {
 	.name = "AC97 HiFi",
 	.playback = {
 		.stream_name = "AC97 Playback",