rtc: max31335: Update adi,max31335.yaml to fix keys

Signed-off-by: Swaroop Kukkillaya <Swaroop.PrakashKumar@analog.com>

Author: SwaroopPKADI

Documentation/devicetree/bindings/rtc/adi,max31335.yaml

@@ -26,12 +26,12 @@ allOf:
       properties:
         reg:
           items:
-            -const: 0x69
+            - const: 0x69
     else:
       properties:
         reg:
           items:
-            -const: 0x68
+            - const: 0x68
 
 properties:
   compatible:
@@ -42,7 +42,7 @@ properties:
   reg:
     description: I2C address of the RTC
     items:
-      -enum: [0x68, 0x69]
+      - enum: [0x68, 0x69]
     maxItems: 1
 
   interrupts: