ARM: dts: gose: enable sound DMA support via SRC in device tree

Enable DMA transfer to/from SRC in r8a7793/gose device tree.

     DMA      DMApp
[MEM] -> [SRC] -> [SSIU] -> [SSI]

     DMA      DMApp
[MEM] <- [SRC] <- [SSIU] <- [SSI]

Current sound driver is supporting
SSI/SRC random connection.
So, this patch is tring
SSI0 -> SRC2
SSI1 <- SRC3

Based on similar work for the r8a7791/koeslch by Kuninori Morimoto.

Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7793-gose.dts

@@ -401,8 +401,8 @@ &rcar_sound {
 
 	rcar_sound,dai {
 		dai0 {
-			playback = <&ssi0>;
-			capture  = <&ssi1>;
+			playback = <&ssi0 &src2>;
+			capture  = <&ssi1 &src3>;
 		};
 	};
 };