ASoC: codecs: jz4725b: Remove unnecessary const qualifier

ASoC: codecs: jz4725b: Remove unnecessary const qualifier

Clang warns:

sound/soc/codecs/jz4725b.c:177:14: warning: duplicate 'const' declaration specifier [-Wduplicate-decl-specifier]
static const SOC_VALUE_ENUM_SINGLE_DECL(jz4725b_codec_adc_src_enum,
             ^
include/sound/soc.h:356:2: note: expanded from macro 'SOC_VALUE_ENUM_SINGLE_DECL'
        SOC_VALUE_ENUM_DOUBLE_DECL(name, xreg, xshift, xshift, xmask, xtexts, xvalues)
        ^
include/sound/soc.h:353:2: note: expanded from macro 'SOC_VALUE_ENUM_DOUBLE_DECL'
        const struct soc_enum name = SOC_VALUE_ENUM_DOUBLE(xreg, xshift_l, xshift_r, xmask, \
        ^

As it points out, SOC_VALUE_ENUM_DOUBLE_DECL has the const attribute in
its definition so remove it here.

Fixes: e9d97b05a80f ("ASoC: codecs: Add jz4725b-codec driver")
Link: https://github.com/ClangBuiltLinux/linux/issues/354
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>