ASoC: dapm: Fix return value of snd_soc_dapm_put_{volsw,enum_virt}()

The ALSA core expect the put callback of a control to return 1 if the value of
the control changed and 0 if it did not. Both snd_soc_dapm_put_volsw() and
snd_soc_dapm_put_enum_virt() currently always returns 0. For both functions we
already have a 'change' variable which either contains 1 or 0 depending on
whether the value has changed or not, so just return that.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>