ASoC: soc-core: Remove unused 'ret' variable

commit 9bde4f0b (ASoC: core: Fix SOC_DOUBLE_RANGE() macros) introduced
the following build warning:

sound/soc/soc-core.c:2999:6: warning: unused variable 'ret' [-Wunused-variable]

Remove the unused 'ret' variable.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/soc-core.c

@@ -2996,7 +2996,6 @@ int snd_soc_get_volsw_range(struct snd_kcontrol *kcontrol,
 	int max = mc->max;
 	unsigned int mask = (1 << fls(max)) - 1;
 	unsigned int invert = mc->invert;
-	int ret;
 
 	ucontrol->value.integer.value[0] =
 		(snd_soc_read(codec, reg) >> shift) & mask;