ASoC: sun8i-codec: Add the AIF2 DAI, widgets, and routes

This adds support for AIF2, which is stereo and has fullly independent
clocking capability, making it very similar to AIF1.
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20201014061941.4306-17-samuel@sholland.orgSigned-off-by: Mark Brown <broonie@kernel.org>