ARM: dts: s5pv210: remove dedicated 'audio-subsystem' node

The 'audio-subsystem' node is an artificial creation, not representing
real hardware.  The hardware is described by its nodes - AUDSS clock
controller and I2S0.

Remove the 'audio-subsystem' node along with its undocumented compatible
to fix dtbs_check warnings like:

  audio-subsystem: $nodename:0: 'audio-subsystem' does not match '^([a-z][a-z0-9\\-]+-bus|bus|soc|axi|ahb|apb)(@[0-9a-f]+)?$'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Jonathan Bakker <xc-racer2@live.ca>
Link: https://lore.kernel.org/r/20200907161141.31034-9-krzk@kernel.org

arch/arm/boot/dts/s5pv210.dtsi

@@ -223,43 +223,36 @@ i2c2: i2c@e1a00000 {
 			status = "disabled";
 		};
 
-		audio-subsystem {
-			compatible = "samsung,s5pv210-audss", "simple-bus";
-			#address-cells = <1>;
-			#size-cells = <1>;
-			ranges;
-
-			clk_audss: clock-controller@eee10000 {
-				compatible = "samsung,s5pv210-audss-clock";
-				reg = <0xeee10000 0x1000>;
-				clock-names = "hclk", "xxti",
-						"fout_epll",
-						"sclk_audio0";
-				clocks = <&clocks DOUT_HCLKP>, <&xxti>,
-						<&clocks FOUT_EPLL>,
-						<&clocks SCLK_AUDIO0>;
-				#clock-cells = <1>;
-			};
+		clk_audss: clock-controller@eee10000 {
+			compatible = "samsung,s5pv210-audss-clock";
+			reg = <0xeee10000 0x1000>;
+			clock-names = "hclk", "xxti",
+				      "fout_epll",
+				      "sclk_audio0";
+			clocks = <&clocks DOUT_HCLKP>, <&xxti>,
+				 <&clocks FOUT_EPLL>,
+				 <&clocks SCLK_AUDIO0>;
+			#clock-cells = <1>;
+		};
 
-			i2s0: i2s@eee30000 {
-				compatible = "samsung,s5pv210-i2s";
-				reg = <0xeee30000 0x1000>;
-				interrupt-parent = <&vic2>;
-				interrupts = <16>;
-				dma-names = "rx", "tx", "tx-sec";
-				dmas = <&pdma1 9>, <&pdma1 10>, <&pdma1 11>;
-				clock-names = "iis",
-						"i2s_opclk0",
-						"i2s_opclk1";
-				clocks = <&clk_audss CLK_I2S>,
-						<&clk_audss CLK_I2S>,
-						<&clk_audss CLK_DOUT_AUD_BUS>;
-				samsung,idma-addr = <0xc0010000>;
-				pinctrl-names = "default";
-				pinctrl-0 = <&i2s0_bus>;
-				#sound-dai-cells = <0>;
-				status = "disabled";
-			};
+		i2s0: i2s@eee30000 {
+			compatible = "samsung,s5pv210-i2s";
+			reg = <0xeee30000 0x1000>;
+			interrupt-parent = <&vic2>;
+			interrupts = <16>;
+			dma-names = "rx", "tx", "tx-sec";
+			dmas = <&pdma1 9>, <&pdma1 10>, <&pdma1 11>;
+			clock-names = "iis",
+				      "i2s_opclk0",
+				      "i2s_opclk1";
+			clocks = <&clk_audss CLK_I2S>,
+				 <&clk_audss CLK_I2S>,
+				 <&clk_audss CLK_DOUT_AUD_BUS>;
+			samsung,idma-addr = <0xc0010000>;
+			pinctrl-names = "default";
+			pinctrl-0 = <&i2s0_bus>;
+			#sound-dai-cells = <0>;
+			status = "disabled";
 		};
 
 		i2s1: i2s@e2100000 {