ASoC: tlv320aic3x: Remove deadlock from snd_soc_dapm_put_volsw_aic3x()

When calling snd_soc_dapm_sync(), it eventually tries to lock the same mutex
already locked in snd_soc_dapm_put_volsw_aic3x() and a deadlock occurs. By
moving the mutex unlock to just before snd_soc_dapm_sync(), this deadlock is
prevented. This problem was introduced in Linux 3.5

Signed-off-by: Andreas Irestål <Andreas.Irestal@axis.com>
Signed-off-by: Mark Brown <broonie@linaro.org>