regulator: rt4801: Fix the dt-binding document for dtc check.

Fix the dt-binding document for dtc check.
Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Link: https://lore.kernel.org/r/1597461262-25878-3-git-send-email-u0084500@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/regulator/richtek,rt4801-regulator.yaml

@@ -49,9 +49,6 @@ required:
   - compatible
   - reg
 
-additionalProperties:
-  - enable-gpios
-
 examples:
   - |
     i2c {