dt-bindings: opp: Fix named microwatt property

The named microwatt-<name> property should look exactly like microvolt
and microamp properties. There were some differences, fix them.
Tested-by: James Calligeros <jcalligeros99@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Documentation/devicetree/bindings/opp/opp-v2-base.yaml

@@ -230,9 +230,9 @@ patternProperties:
         minItems: 1
         maxItems: 8   # Should be enough regulators
 
-      '^opp-microwatt':
+      '^opp-microwatt-':
         description:
-          Named opp-microwatt property. Similar to opp-microamp property,
+          Named opp-microwatt property. Similar to opp-microamp-<name> property,
           but for microwatt instead.
         $ref: /schemas/types.yaml#/definitions/uint32-array
         minItems: 1