ASoC: codecs/jz4770: Add DAPM widget to set HP out to cap-less mode

Cap-less mode is useful e.g. if the headphones are used as an antenna
for a FM radio, so that the signal is not altered. For everything else,
we want the cap-couple mode.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20201207125338.119397-5-paul@crapouillou.net
Signed-off-by: Mark Brown <broonie@kernel.org>