ASoC: dt-bindings: simple-card: Fix 'make dt_binding_check' warnings

The following build warnings are seen with 'make dt_binding_check':

Documentation/devicetree/bindings/sound/simple-card.example.dts:209.46-211.15: Warning (unit_address_vs_reg): /example-4/sound/simple-audio-card,cpu@0: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:213.37-215.15: Warning (unit_address_vs_reg): /example-4/sound/simple-audio-card,cpu@1: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:250.42-261.15: Warning (unit_address_vs_reg): /example-5/sound/simple-audio-card,dai-link@0: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:263.42-288.15: Warning (unit_address_vs_reg): /example-5/sound/simple-audio-card,dai-link@1: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:270.32-272.19: Warning (unit_address_vs_reg): /example-5/sound/simple-audio-card,dai-link@1/cpu@0: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:273.23-275.19: Warning (unit_address_vs_reg): /example-5/sound/simple-audio-card,dai-link@1/cpu@1: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:276.23-278.19: Warning (unit_address_vs_reg): /example-5/sound/simple-audio-card,dai-link@1/cpu@2: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:279.23-281.19: Warning (unit_address_vs_reg): /example-5/sound/simple-audio-card,dai-link@1/cpu@3: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/sound/simple-card.example.dts:290.42-303.15: Warning (unit_address_vs_reg): /example-5/sound/simple-audio-card,dai-link@2: node has a unit name, but no reg or ranges property

Fix them all.

Signed-off-by: Fabio Estevam <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

Documentation/devicetree/bindings/sound/simple-card.yaml

···
   - |
     sound {
         compatible = "simple-audio-card";
+        #address-cells = <1>;
+        #size-cells = <0>;
 
         simple-audio-card,name = "rsnd-ak4643";
         simple-audio-card,format = "left_j";
···
                                     "ak4642 Playback", "DAI1 Playback";
 
         dpcmcpu: simple-audio-card,cpu@0 {
+            reg = <0>;
             sound-dai = <&rcar_sound 0>;
         };
 
         simple-audio-card,cpu@1 {
+            reg = <1>;
             sound-dai = <&rcar_sound 1>;
         };
 
···
   - |
     sound {
         compatible = "simple-audio-card";
+        #address-cells = <1>;
+        #size-cells = <0>;
 
         simple-audio-card,routing =
             "pcm3168a Playback", "DAI1 Playback",
···
             "pcm3168a Playback", "DAI4 Playback";
 
         simple-audio-card,dai-link@0 {
+            reg = <0>;
             format = "left_j";
             bitclock-master = <&sndcpu0>;
             frame-master = <&sndcpu0>;
···
         };
 
         simple-audio-card,dai-link@1 {
+            reg = <1>;
             format = "i2s";
             bitclock-master = <&sndcpu1>;
             frame-master = <&sndcpu1>;
 
             convert-channels = <8>; /* TDM Split */
 
-            sndcpu1: cpu@0 {
+            sndcpu1: cpu0 {
                 sound-dai = <&rcar_sound 1>;
             };
-            cpu@1 {
+            cpu1 {
                 sound-dai = <&rcar_sound 2>;
             };
-            cpu@2 {
+            cpu2 {
                 sound-dai = <&rcar_sound 3>;
             };
-            cpu@3 {
+            cpu3 {
                 sound-dai = <&rcar_sound 4>;
             };
             codec {
···
         };
 
         simple-audio-card,dai-link@2 {
+            reg = <2>;
             format = "i2s";
             bitclock-master = <&sndcpu2>;
             frame-master = <&sndcpu2>;