ASoC: WM8904: Set `invert' bit for Capture Switch

Set `invert' bit for Capture Switch. Otherwise analogue is muted when
Capture Switch is ON.

Signed-off-by: Hong Xu <hong.xu@atmel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org