ASoC: meson: Remove unused declartion in header file

The declaration of aiu_fifo_hw_free() has been removed since
commit e05cde84 ("ASoC: meson: Use managed DMA buffer allocation").
Let's remove the unused declaration.

Fixes: e05cde84 ("ASoC: meson: Use managed DMA buffer allocation")
Signed-off-by: Zhang Zekun <zhangzekun11@huawei.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://patch.msgid.link/20240910122330.70684-1-zhangzekun11@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/meson/aiu-fifo.h

@@ -38,8 +38,6 @@ int aiu_fifo_prepare(struct snd_pcm_substream *substream,
 int aiu_fifo_hw_params(struct snd_pcm_substream *substream,
 		       struct snd_pcm_hw_params *params,
 		       struct snd_soc_dai *dai);
-int aiu_fifo_hw_free(struct snd_pcm_substream *substream,
-		     struct snd_soc_dai *dai);
 int aiu_fifo_startup(struct snd_pcm_substream *substream,
 		     struct snd_soc_dai *dai);
 void aiu_fifo_shutdown(struct snd_pcm_substream *substream,