ASoC: rockchip: put device_node on remove

snd_rk_mc_probe() gets a couple of device nodes with of_parse_phandle(),
but there is no release of them.

The patch adds remove handler and proper error handling in the probe.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Mark Brown <broonie@kernel.org>