ASoC: sun4i-spdif: Add support for H6 SoC

Allwinner H6 has a different mapping for the fifo register controller.

Actually only the fifo TX bit is used in the drivers.

Use the freshly introduced quirks to make this drivers compatible with
the Allwinner H6.

Signed-off-by: Clément Péron <peron.clem@gmail.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>