ASoC: tegra: tegra20_das: Get rid of global pointer for driver data

This enables the driver (at least theoretically) to bind to more than one
device.

The remove function has nothing to do now, so it is dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220629194224.175607-3-u.kleine-koenig@pengutronix.de


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