ASoC: Tegra TrimSlice machine: Use devm_ APIs and module_platform_driver

module_platform_driver saves some boiler-plate code.

The devm_ APIs remove the need to manually clean up allocations,
thus removing some code.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>