ASoC: tlv320adcx140: Add digital mic channel enable routing

Add the audio routing map to enable the digital mic paths when the
analog mic paths are not enabled.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Link: https://lore.kernel.org/r/20200828112855.10112-1-dmurphy@ti.com


Signed-off-by: Mark Brown <broonie@kernel.org>