ASoC: soc.h: remove unnecessary definitions

#define SOC_ENUM_SINGLE_VIRT_DECL(name, xtexts) \

	const struct soc_enum name = SOC_ENUM_SINGLE_VIRT(ARRAY_SIZE(xtexts), xtexts)

struct snd_jack;

struct snd_soc_card;

struct snd_soc_pcm_stream;

struct snd_soc_ops;

struct snd_soc_pcm_runtime;

struct snd_soc_dai;

struct snd_soc_dai_driver;

struct snd_soc_dai_link;

struct snd_soc_component;

struct snd_soc_component_driver;

struct soc_enum;

struct snd_soc_jack;

struct snd_soc_jack_zone;

struct snd_soc_jack_pin;

#include <sound/soc-dapm.h>

#include <sound/soc-dpcm.h>

#include <sound/soc-topology.h>

struct snd_soc_jack_gpio;

enum snd_soc_pcm_subclass {

	SND_SOC_PCM_CLASS_PCM	= 0,

	SND_SOC_PCM_CLASS_BE	= 1,