ASoC: rockchip: Fix an error handling in 'rockchip_i2s_probe'

If this memory allocation fail, we must disable what has been enabled.
Do not return immediately but go thrue the error handling path instead.

Also use 'devm_kmemdup' instead of 'devm_kzalloc+memcpy' to simplify code.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>