ASoC: rockchip: add config for rockchip dmaengine pcm register

This patch makes the rockchip i2s pcm configurable by adding
rockchip pcm config for devm_snd_dmaengine_pcm_register.

Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>