dt-bindings: clock: brcm,iproc-clocks: fix armpll properties

armpll clocks (available on Cygnus and Northstar Plus) are simple clocks
with no cells. Adjust binding props #clock-cells and clock-output-names
to handle them.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Link: https://lore.kernel.org/r/20210819052918.6753-1-zajec5@gmail.comAcked-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Documentation/devicetree/bindings/clock/brcm,iproc-clocks.yaml

@@ -62,13 +62,30 @@ properties:
     maxItems: 1
 
   '#clock-cells':
-    const: 1
+    true
 
   clock-output-names:
     minItems: 1
     maxItems: 45
 
 allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - brcm,cygnus-armpll
+              - brcm,nsp-armpll
+    then:
+      properties:
+        '#clock-cells':
+          const: 0
+    else:
+      properties:
+        '#clock-cells':
+          const: 1
+      required:
+        - clock-output-names
   - if:
       properties:
         compatible:
@@ -359,7 +376,6 @@ required:
   - reg
   - clocks
   - '#clock-cells'
-  - clock-output-names
 
 additionalProperties: false
 
@@ -393,3 +409,10 @@ examples:
         clocks = <&osc2>;
         clock-output-names = "keypad", "adc/touch", "pwm";
     };
+  - |
+    arm_clk@0 {
+        #clock-cells = <0>;
+        compatible = "brcm,nsp-armpll";
+        clocks = <&osc>;
+        reg = <0x0 0x1000>;
+    };