ASoC: sun4i-codec: Add custom regmap configs

The A20 has a few extra registers that the A10 doesn't have.
Therefore, use different regmaps for A10 as compared to A20.

Signed-off-by: Danny Milosavljevic <dannym@scratchpost.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>