ASoC: nau8540: Add pre-charge actions for input

Adding pre-charge mechanism to make FEPGA power stable faster. It
not only improved the recording quality at the beginning but also
meaningfully decreased the final adc delay time.

Signed-off-by: David Lin <CTLIN0@nuvoton.com>
Link: https://msgid.link/r/20240116024519.24569-1-CTLIN0@nuvoton.com


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