* Spreadtrum sound pcm platform driver

This node models spreadtrum sound pcm platform driver

Required properties:

- compatible : "sprd,sharkl5-pcm-platform", "sprd,roc1-pcm-platform", "sprd,sharkl3-pcm-platform",
	"sprd,sharkl5pro-pcm-platform",sprd,7731e-pcm-platform
- dmas : pcm platform used dma channels
- dma-names : dma names of dma channels
- #sound-dai-cells : only support 0, it means use default
	asoc platform.

dmas and dma-names have a one-to-one correspondence.

Example:
sprd_pcm: sprd-pcm-audio {
	compatible = "sprd,sharkl5-pcm-platform";
	#sound-dai-cells = <0>;
	dmas = <&agcp_dma 1 &agcp_dma 2
		&agcp_dma 3 &agcp_dma 4
		&agcp_dma 5 &agcp_dma 6
		&agcp_dma 7 &agcp_dma 8
	dma-names =
		"normal_p_l", "normal_p_r",
		"normal_c_l", "normal_c_r",
		"normal23_p_l", "normal23_p_r",
		"normal23_c_l", "normal23_c_r";
};

sprd-audio-card,dai-link@1 {
	...
	plat {
		sound-dai = <&sprd_pcm>;
	};
	...
};
