ASoC: wm8994: Replace usage deprecated MUX/ENUM macros

SND_SOC_DAPM_VIRT_MUX, SND_SOC_DAPM_VIRT_MUX_E and SOC_DAPM_ENUM_VIRT are
deprecated and merely an alias for SND_SOC_DAPM_MUX, SND_SOC_DAPM_MUX_E and
SOC_DAPM_ENUM. Replace the deprecated macros so we can eventually remove their
definition.

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