ASoC: rsnd: adjust disabled module

In general Renesas SoC's SSI/SRC are all enabled, but some SoC is not.

	H2	E2

	SRC0	      <=
	SRC1	SRC1
	SRC2	SRC2
	...	...

Renesas Sound driver is assuming that *all* modules are
enabled, and thus it is using *data array* to access each modules.
Because of it, we have been using "status = disabled" at DT,
and using *full size* array but avoiding disabled module.

ex)
	rcar_sound,src {
		src-0 {
=>			status = "disabled";
		};
		src1: src-1 {
			...
		};
		...

But R-Car D3 have many disabled modules (It has SSI3/SSI4, SRC5/SRC6),
and Renesas SoC maintainer don't want above style on DT.

ex)
	rcar_sound,src {
=>		src0: src-0 { status = "disabled"; };
=>		src1: src-1 { status = "disabled"; };
=>		src2: src-2 { status = "disabled"; };
=>		src3: src-3 { status = "disabled"; };
=>		src4: src-4 { status = "disabled"; };
		src5: src-5 {
			...
		};
		src6: src-6 {
			...
		};
	};

	rcar_sound,ssi {
=>		ssi0: ssi-0 { status = "disabled"; };
=>		ssi1: ssi-1 { status = "disabled"; };
=>		ssi2: ssi-2 { status = "disabled"; };
		ssi3: ssi-3 {
			...
		};
		ssi4: ssi-4 {
			...
		};
	};

To adjust it, it needs to care about related for_each_child_of_node()
loop on rsnd driver, and it is used from...

	> grep -l for_each_child_of_node sound/soc/sh/rcar/*
	sound/soc/sh/rcar/core.c
	sound/soc/sh/rcar/ctu.c
	sound/soc/sh/rcar/dma.c
	sound/soc/sh/rcar/dvc.c
	sound/soc/sh/rcar/mix.c
	sound/soc/sh/rcar/src.c
	sound/soc/sh/rcar/ssi.c
	sound/soc/sh/rcar/ssiu.c

This patch adjust to this situation.
By this patch, we can avoid disabled modules on DT

	rcar_sound,src {
		src5: src-5 {
			...
		};
		src6: src-6 {
			...
		};
	};

	rcar_sound,ssi {
		ssi3: ssi-3 {
			...
		};
		ssi4: ssi-4 {
			...
		};
	};

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/875yyzk017.wl-kuninori.morimoto.gx@renesas.com


Signed-off-by: Mark Brown <broonie@kernel.org>